With three-eighths to travel, Stopchargingmaria began to lengthen her stride, and she quickly inhaled Miss Besilu and Taketheodds, taking the lead before the quarter pole and drawing clear under Javier Castellano's drive to win by five widening lengths over Unbridled Forever, who passed tiring rivals to finish second.
The final time for 1 1/8 miles was 1:49.80. Stopchargingmaria, who is owned by Mike Repole, returned $4.40 for a $2 win wager.
"I had a beautiful dream trip," said Castellano. "My concerns were the small field and the one hole, which is sometimes difficult to get out. I'm glad it worked out perfect. I saved the ground on the first turn. After that I secured my spot. I like the way she did it today. Turning for home, I was thinking the race was over. At the top of the stretch, she took off. Now, the way she has matured, she was phenomenal today."
Stopchargingmaria began her career at Saratoga last summer with an easy maiden victory and a runner-up performance in the Grade 1 Spinaway. After finishing third in the Grade 1 Frizette at Belmont, she concluded her juvenile season with wins in the Grade 3 Tempted and Grade 2 Demoiselle at Aqueduct Racetrack.
She disappointed in her first two starts in 2014, finishing fifth in the Grade 2 Davona Dale at Gulfstream Park and fourth in the Grade 3 Fantasy at Oaklawn Park, before she regained winning form with her Black-Eyed Susan score on May 16.
"I told Mike that this filly has never trained better than she has here in the last month," said trainer Todd Pletcher. "She seems to really like Saratoga. She has been training much more powerfully than she did this winter, so we expected a big effort from her."
Overall, Stopchargingmaria is 5-1-1 in nine starts. The $180,000 winner's share of the Coaching Club American Oaks purse pushed her lifetime earnings into the seven figures at $1,054,000.
It was the sixth Coaching Club American Oaks triumph for Pletcher, who has won the race three times since the race was moved to Saratoga in 2010. Pletcher and Castellano won last year's edition with Princess of Sylmar, who went on to take the Grade 1 Alabama later in the meet.
"The huge thing was to win a Grade 1 [with Stopcharingmaria]," said Pletcher. "A filly of her résumé to get that Grade 1 was huge. I thought she ran well enough today to certainly earn a spot in the Alabama [Grade 1, $600,000 August 16]."
Miss Besilu was third, followed by America, Taketheodds, and Courageous Julie, who ran for purse money only.