Boyd Martin and Tsetserleg. Photo by Erin Gilmore Photography.Editors Note: This article will be updated with additional photos soon, so keep checking back!Up to snuff and up to standard were terms we heard often when describing Jay Hamblys Advanced Championship cross country course at the USEA American Eventing Championships today. Hosting the AECs at the iconic Kentucky Horse Park, particularly at the Advanced level, feels akin to the Defender Kentucky Three-Day Event, and indeed we were left feeling like wed just watched part of the 5* track in many ways.And as such, we saw plenty of expected influence today, with nearly all of the original top-placed competitors changing places, primarily due to time penalties though several fences did catch many pairs out as the competition came to a close for the day in this division.First things first, many will be wanting updates on Liz Halliday after she had a hard fall with Shanroe Cooley at fence 21. Her team and the USEA have put out a statement:After a fall on cross-country at fence 21b in the $60,000 Adequan USEA Advanced Final this morning at the USEA American Eventing Championships (AEC) presented by Nutrena Feeds, Liz Halliday was transported to the University of Kentucky Medical Center for evaluation. Halliday was transported to the University of Kentucky Medical Center where they are providing care and treatment.Shanroe Cooley, owned by The Ocala Horse Properties LLC, was assessed by the veterinary team on-site and was uninjured in the fall.The USEA, EEI, and Mary Fike send Halliday our best wishes.We are pulling hard for Liz, as are her fellow competitors who have all expressed their care for her as we did their post-ride interviews, and will provide updates on her condition as they are made available to us. Please respect her and her teams privacy at this time.Boyd Martin Holds Firm with TsetserlegBoyd Martin knew exactly where he needed to be with the Turner familys Tsetserleg (Windfall Thabana, by Buddenbrock) as he set out on course toward the end of the running order. He would have about 29 seconds in hand to best Will Coleman and Diabolos finishing score of 35.6, and used up 22 of those seconds to stop the clock with 8.8 time penalties added. His two-phase score of 32.8 would be enough to hold him in first place ahead of show jumping under the lights tomorrow.Thomas was a vintage Tsetserleg, Boyd remarked. The biggest challenge we had is he was, you know, attacking the fences, and I felt like all the way around he was brave as a lion. I was trying to slow him down and steady him up without wrestling him too much. But all in all, hes such a experienced, seasoned campaigner. I think every time hes been at the Kentucky Horse Park, he knows its time to go. So he was full of running and all in all, gave me a fantastic round.I think he built a challenging track, Boyd continued about Jay Hamblys course design. There were lots of questions [that] really tested your rideability and your turning and it was what I think was sort of a four and a half star FEI, four and a half star short, if that makes any sense. Jay Hambly, similar to Derek di Grazia and Ian Stark in the design, he builds forward distances and big jumps, and I feel like hes got a real gift of sort of these discreet little traps that he sets around the course. View this post on InstagramA post shared by Boyd Martin (@boydmartineventing)Thomas has historically struggled in the final phase, and not for a lack of effort on the part of both Boyd and his jumping coach Peter Wylde. The Trakehner gelding has jumped two clear rounds at Advanced this year. He does not have a rail in hand over Will and Diabolo, but a clear round would see Boyd hoist the Adequan Advanced trophy and take home the lions share of the $60,000 prize fund.Boyd has ownership two of the top three spots this afternoon, also piloting Yankee Creek Ranch LLCs Commando 3 (Connor 48 R-Adelgunde, by Amigo xx) to a clear round with 8 time penalties to sit on a score of 36.0 in third overnight. Connor is preparing to step up to the 5* level at the Maryland 5 Star this October.Conner was absolutely brilliant, Boyd said. I think hes one of the best horses in the world. Hes had sort of a long preparation to be ready to go to the Olympics. And sadly, for Conner, he didnt get his chance to show his stuff in Paris. And he did it quite easy today.Ive been having him ultra prepared to step in at any minute. We had him very fit and schooled up and ready to rumble for last month. So he felt brilliant and Im just so excited for the future with Conner. Hes just an amazing animal.Diabolo Delivers a Strong Prep for MarylandWill Coleman told us yesterday that he didnt have grand plans for the 12-year-old Diabolo (Diarado Roulett M, by Aljano 2) this week. His main priority this week has been knocking off the inevitable cobwebs that come from not getting in a strong rule for a couple of months, and his cross country ride with Dab accomplished this.My goal was really just to give him a nice round, Will said. About 20 seconds of time is what I had aimed for. This event is just one step towards a bigger goal at Maryland [5 Star], but I was happy with how my horse responded.I thought the ground, theyve done an amazing job preparing it. The conditions really couldnt have been worse with how hot and dry its been, so all credit to Jay [Hambly] and Tyson [Rementer] and Mick [Costello] and the whole team that really made the most out of the ground out there. Its still firm but we really appreciate their efforts.Diabolo is a horse that Wills had to establish a partnership with; the horse previously campaigned through this level with Australian rider Gemma Tinney before making his way to the Northern Hemisphere and his new rider early in 2023. He dealt with some health issues from the acclimation, but from that point on Wills seen the horse grow in both his body as well as his mind, ultimately taking the victory in the tough Lexington 4*-S during Kentucky weekend this spring.I think any horse you get, theres just always this kind of 12 to 18 months where you have to invest in them to let them learn your system, he said. Let them kind of acclimate to your way of doing things, and vice versa, youre doing the same in response to the horse. So I think some of the foundational stuff we were trying to establish has become established, and now theres a lot of trust and understanding between us, and the communication is getting a lot better.Will and Diabolo will go into tomorrows finale on a score of 35.6 with 7.6 time penalties added to their dressage score. Diabolo was second here at AEC in 2023 in the Intermediate Championship and has a strong show jumping record to challenge Boyd for the overall win.Dutton, Klugman, Wildasin Ride to Strong Top 6 RoundsPhillip Dutton was pleased with the efforts of the Possante Groups Possante (Namelus R Wendelien, by Otangelo) today, jumping clear with 10.8 time penalties to secure fourth place overnight on a score of 39.4. This is another newer ride on Phillips string, having formerly been campaigned through the 4* level by Great Britains Emily King. For Phillip, the process of building this horse up for competitive finishes at this level has been about producing him to the point where speed becomes possible due to rideability and a quickness in the mind.Thats probably the quickest Ive taken him, and he handled it pretty well, he said. The faster you go, the more risk you take. So firstly, the priority for me is they have to have a base of fitness and the biggest errors Ive made are running a horse fast when they arent conditioned enough for it. So its making sure they are strong enough and [rideable enough], and mentally the horse has to be able to accept, or maybe not accept but not get flustered by going at that speed and still keep a clear mind and thats where I was very pleased with Impy today. Right to the end he was pretty alert and still very adjustable and able to read the jumps.Phillip has applied for the Military Boekelo CCIO4*-L in October but if hes not selected for the U.S. traveling squad hell aim Possante for the 4*-L at Morven Park instead. He also expressed his thoughts for Liz. Its been an up and down day with Lizs fall, and our thoughts are with her and her family, he said.Ema Klugman was also pleased with the speed she was able to show with Bronte Beach Z (Verdi TN Dalphine, by Chopin), who debuted at the 5* level in April at Kentucky and has been building that all-important cumulative base of fitness as she looks ahead to a second 5* start at Maryland in October. Ema stopped the clock with 6.4 time penalties added for a score of 39.6 and fifth place overall after two phases.If you had told me six months ago that she wouldve been one of the fastest horses here I wouldve been surprised! Ema said, describing todays course as essentially like riding the second half of Kentuckys 5* track with its terrain and three big uphill pulls.I was glad both of my horses have really big strides because I think it was easier to do just riding forward, Ema said. And if they have a big stride, you can just keep on cruising and the jumps come up well versus being on a smaller stride horses and having to add a lot.Ema noted that shes enlisted the perspective of many of her fellow upper-level riders as shes built and evolved her fitness program. With four horses currently running at Advanced this season, each horse is on its own individual program. [Bronte Beach Z]doesnt have a ton of blood but weve been working hard on her fitness, she elaborated. Anything with horses and the sport is you kind of change your system over time and try different things and see what works best.I think the first part is that fitness is cumulative so over time the horse will just get fitter, but I also think its interesting in other sports, theres maybe more open intel about how people train, Ema continued. Everyone who trains for a marathon can just kind of Google a regimen for training. Whereas thats not really readily available, certainly not just randomly on the internet, for eventing horses.I did a little bit of asking different people what they do in terms of preparing horse for Kentucky or other events. I didnt necessarily adopt any one of those approaches but I took it into account.For her, were adopting more faster work, but also doing the slow long sets as well so its kind of a combination. But really I think shes just growing up a bit so Im able to push her little harder. Its a balance because the risk of injury is higher when you go fast in training, but if you dont teach them to go fast then they have trouble in competition. And Im learning as we go too, so I dont think Ive fully cracked it. But well see if she can maintain that pace around a longer course.The sole rider to catch the time today did not in fact wear a watch for cross country. Arden Wildasin told me she hasnt worn a watch on cross country in about two years, preferring to rely on how her horses feel underneath her and achieve a natural pace. That approach certainly paid off today as she delivered a clear round with her own and her familys Sunday Times (Cult Hero Lackaghbeg Crest, by Sea Crest) nearly bang on the optimum of 6:27.At 18 years young, Mumbles certainly knows his way around an Advanced track at this point, and Ardens been working hard on achieving the polish she needs to execute fast and, most importantly, smooth rounds.I knew from riding the two Intermediate horses that the time would be hard to make, but I knew that Mumbles was fit and ready to run and I left the box saying go at your speed and I know thats fast, Arden said. Sometimes I will go slow because its not the right time or somethingwhere its moreof a homework aspect I need to work on, so in that aspect I dont need to worry about the time. Versus here at a championship, its a gallopingcourse and youve put your homework in thats why youre here. Trust yourself, trust your horse, and go out and gallop.You leave the start box knowing what youre sitting on that day and what stride length you can achieve, Arden said, describing how she wound up taking the option at the coffin late on course after Sunday Times stumbled after the ditch. Maybe what you walked isnt what you rode, but it is the path that you planned out. It might be leaving a stride or adding one because he jumped rounder than what I wanted or thought he would. So numbers should go out the window for you and you ride from jump to jump, in the combinations, in the singles, as smooth and effortlessly as you can. But if you can be fluid and soft, your horse will come out of it wanting to keep going again and again.Arden is ticking off the qualifications she needs to step up to 5* with this horse and to that end is aiming for the 4*-L at Morven Park. If shes successful there, she will have done arguably the two toughest 4*-L tracks in the country to set her up well for a 5* debut. This possibility, she says, is all in credit to her horse of a lifetime.He is definitely a cross country machine, she said. He is special. Hes given me the mileage and confidence to go around and tackle big, huge, challenging courses. I know every course I face there is going to be a challenge, so with my head on straight if I can ride him well, he can tackle anything and hes confident in himself and nimble and quick with his feet. Hes a horse that we didnt know if he would go Advanced. With horses, you dont know if Advanced is there. I think Intermediate you do, but its that next gear for Advanced where the pressure and technical skills are higher and its a question of does this horse have that?. And hes special. Our dressage needs work, well keep on working on that, but Ill take any qualifying dressage score to get to go out and run every cross country course. He is so special to me.Hamblys Build Tests Championship MettleJay Hamblys course, with which he was ably assisted by a team of builders including Tyson Rementer and Mick Costello, received high praise from all of the riders, and it certainly exerted a strong influence on the standings.The most influential fence was fence 14, the Nutrena Narrows, which consisted of an A B C D combination that Arden Wildasin described as a four-jump serpentine. The combination of slight terrain changes and challenging related distances caught out several pairs, including early third-placed Sharon White and Claus 63 (Sharon was of course disappointed with this, but was overall chuffed with Claus for how well he went around the rest of the course).It actually reminded me of the water jump there at Kentucky in 2021, Ema Klugman observed. You had a similar thing where you went in the water and onto an island where there was an arrowhead. I would say that was almost easier because it was on a straight line. This one was turning. Theyre big arrowheads so you cant add a stride. I almost thought maybe I should go out [and add a stride], but then I thought both of these horses have massive strides so why would I add a stride? The whole point of having horses with a big stride is you can keep on riding forward at those type of questions. Its good to have things that are that hard.In total, seven combinations encountered trouble at this fence, primarily at the C element.Tomorrow well see this Advanced division wrap up with show jumping in the iconic Rolex Stadium beginning at 6:45 p.m. EST. As always you can view the action across divisions live on Horse & Country here. Well add additional press releases from the USEA on the other divisions below, or you can catch up with their teams hard work on useventing.com.USEA Coverage LinksA Lot to Love About P.S. I Love You After Cross-Country in the #AEC2024 USEA Open Intermediate ChampionshipFour ARMA USEA Training Championships Dance in the Dressage Rings at the #AEC2024USEA American Eventing Championships: [Website] [Schedule] [Live Stream] [Timing & Scoring] [Volunteer] [Official Photographer] [XC Courses]ENs remote coverage of #AEC2024 is brought to you by Ride Equisafe, who is on site in the vendor fair at the Horse Park this week to help you with all of your safety equipment needs! You can also shop online (and contact them for bespoke recommendations) here.