When watching the race initially, something seemed "off" a bit even with Katelyn leading by an open margin ... In all the race videos I've watched of Katelyn during XC and this indoor track season, Katelyn typically ran fast with minimal effort and straining ... At Millrose, she seemed to be forcing her pace noticeably and seemed to be running a bit tighter than normal ... That was also my opinion after watching the full race video several times at USATF.tv.
Her coach's reaction was noted in a newspaper article in Lohud noted below.
Race winner Gabrielle Wilkinson has been very impressive during indoor ... Kelsey Chmiel now has head-to-head wins over both Katelyn Tuohy and Claudia Lane in major races.
From the newspaper article Link:
https://www.lohud.com/story/sports/high-school/track/2018/02/03/stunner-tuohy-loses-lead-and-millrose-mile-during-last-lap-flynn-w-personal-best/1089108001/
"Despite her lead, Diglio knew early on something was wrong.
Aiming to break 4:40, she was behind her projected 800-meter split by three seconds, he noted. She completed 809 meters in 2:19.18.
Diglio rushed to the finish well before Tuohy relinquished her lead, worried she was injured.
In fact, his concern began after just 400 meters.
He said after the race she reported she never felt right but was unhurt.
“She was struggling from the beginning,” Diglio said. … “She didn’t have it.”
But Diglio also credited her opponents in the 13-athlete race, saying they had run smart and never allowed Tuohy to get too far in front.
“You show any weakness and they’ll pounce,” he said.
“It’s a tough loss for Katelyn,” Diglio said. “You don’t always win. Part of being a great runner is learning how to lose. This is pretty big adversity today and a bitter pill to swallow.”"