By Jake Donovan

Keith Thurman survived his toughest test to date, overcoming a broken nose and outlasting Diego Chaves to score a 10th round knockout in their welterweight war Saturday evening in San Antonio, Texas.

The bout began as a slugfest, which suggested a significant advantage for the visiting Argentine slugger. Thurman answered any lingering questions about his chin, eating an alarming number of right hands, including one that busted open his nose in the third round.

Momentum changed in round four and never really slipped away from Thurman's grasp. The American boxer-puncher made subtle adjustments to minimize the impact of Chaves' blows, while always being in position to fire back.

Chaves began to slow in the middle rounds, which Thurman suggested was around which he built his strategy.

"I saved my best tools for the later rounds," Thurman (21-0, 19KO) suggested after the win, which netted him an interim welterweight belt. "I knew he would be in beautiful condition early on but that he would eventually die out. That's when I hit him with that beautiful body shot."

The body shot to which he refers caught Chaves right on the sweet spot in round nine, forcing him to a knee for the first of the bout's two knockdowns. Thurman immediately jumped on his wounded prey early in the 10th, forcing him to the deck where Chaves remained for the full ten count and beyond.

The loss is the first for Chaves, who falls to 22-1 (18KO).

Thurman was overjoyed in scoring the biggest win of his young career, though for a brief moment forgetting where he was.

"I'd like to thank this beautiful city. Thank you, San Diego," Thurman shouted, before realizing his gaffe. "San Antonio, I mean. San Antonio!"

Geography challenge aside, Thurman answered a lot of lingering questions surrounding his career. He has also outpaced the entire 2008 U.S. Olympic boxing squad, of which he was one win away from joining before losing to Demetrius Andrade in the U.S. Olympic Trials finals.

Andrade is being groomed for a vacant title fight with Vanes Martirosyan - a member of the 2004 U.S. Olympic boxing squad - later this year. By then, Thurman should have a firm grasp on his future.

Until then, he gets to savor life in the present, where he is now an official player in a lucrative welterweight division.

Jake Donovan is the Managing Editor of Boxingscene.com, as well as the Records Keeper for the Transnational Boxing Ratings Board and a member of Boxing Writers Association of America. Twitter: @JakeNDaBox