Sam Querrey beat 14-time Grand Slam champion Rafael Nadal in straight sets to claim the ATP Mexico Open title on Saturday.
The American clinched the final 6-3 7-6 to secure the title despite being unseeded and ranked No 40 in the world.
Querrey, 29, beat Nadal for the first time in five meetings between the pair, powering home 19 aces as the Spaniard had no answer to his power.
Nadal, 30, was looking for his 70th career victory and had marched to the final in Mexico without dropping a set, but within 29 minutes he was on the backfoot with Querrey already a break ahead.
Nadal responded in the second set with the support of the majority of the Acapulco crowd, but somehow failed to take any of the six break point opportunities he created for himself, five of which came in the crucial eighth game, as he ultimately lost out via a tiebreak 7-6.
Querrey neutralised three of those break points with aces before a couple of baseline errors from Nadal allowed the American to serve out the victory.
Elsewhere, Great Britain’s Jamie Murray combined with Bruno Soares of Brazil to secure their first ATP doubles title of 2017 at the Abierto Mexicano Telcel, beating John Isner and Feliciano Lopez 6-3 6-3 for their fourth title since the pair teamed up last year.
“We did well to win the first match this week (against Cilic/Mektic) because we were down for most of the match tie-break,” said Murray. “But that’s what often happens in doubles. You squeeze through the first match and go on to win the tournament.”