COLORADO SPRINGS, Colo. -- Army boxer DeAndrey Abron rallied late in the final round for a 27-26 win over Jaidon Codrington on Thursday in the quarterfinals of the U.S. Amateur Boxing Championships.

With the score tied at 26 in the fourth and final round of the heavyweight bout, Abron connected on an overhand right late in the round that proved the difference.

"He was setting up for his big right hand, that's why he dropped his left. He was loading up with his right hand, and I just let mine go and my speed just got there first," said Abron, who is ranked fourth nationally at light-heavyweight by USA Boxing. "I saw (the opening) and I had nothing to lose and everything to gain."

The top two finishers in each weight class at the amateurs qualify for the U.S. Olympic team trials in February in Mississippi.

Abron, of Fort Carson, Colo., used his speed and midrange boxing skills to outduel Codrington, a New Yorker, and take a 17-12 lead after the first two rounds.

In the third round, Abron tried to match Codrington's brawling style.

"I didn't want to brawl with him," Abron said. "But I did want to test his gas and I guess the only way to do that was to stand there and exchange punches with him."

In the third and fourth rounds, Codrington connected on left hooks and overhand rights, inflicting a bloody nose and three standing 8-counts on Abron.

Codrington controlled the tempo until Abron's big overhand right landed with just seconds remaining.

After the fight, a shocked Codrington left the ring in tears, while his fans chanted, "Fix! Fix! Fix!"

In the night's only bout between two ranked opponents, light welterweight Devon Alexander, ranked fourth by USA boxing in his weight class, defeated No. 9 Dominic Chavez 26-10.

Alexander, a 17-year old from St. Louis with nine years of ring experience, used lightning combinations to stifle Chavez.

"I don't like to throw just one punch," Alexander said. "I like to throw three."

In a mild upset, unranked super heavyweight Greg Corbin, of Dallas, won a 21-20 decision over No. 8 Michael Marrone.