Juan Monaco beat Jack Sock 3-6, 6-3, 7-5 to win his second Houston title on Sunday.
The Argentine will climb in the ATP Rankings from No. 148 to No. 86.
“I didn't expect this so fast,” Monaco said who had wrist surgery in August. “No words to describe this moment.”
Sock breezed through the first set, winning 65 per cent of his service points to claim the opener in about 30 minutes but then Monaco won 10 of the next 14 games.
The American fell behind 4-1 in the third but back to win four consecutive games, erase a double-break deficit and lead the third set, 5-4.