Taylor Fritz saved two match points as he stunned world No 4 Alexander Zverev to book his place in the semi-finals of the BNP Paribas Masters in Indian Wells.
The American world No 39 rallied from the brink of defeat when Zverev served for the match at 5-3 in the final set, before surging through a decisive tie-break to triumph 4-6, 6-3, 7-6.
Zverev had looked set to consolidate his stellar hard-court campaign, which included Olympic gold and a title in Cincinnati, when he broke early to take the first set.
Fritz fought back to level the match but it was the Russian who seized an early advantage in the decider and looked set to complete a hard-fought win, setting up two separate match points at 5-3.
But Fritz was far from done, breaking back and forcing the tie-break in which he raced into a 6-1 lead, finally ending their two hours and 20 minute tussle on his third match point opportunity.
In the last four Fritz will face Nikoloz Basilashvili, who scored another upset with a 6-4, 2-6, 6-4 win over world No 3 Stefanos Tsitsipas.
Basilashvili broke Tsitsipas in the opening game of the match and maintained his advantage to take the first set, but the momentum swung in the second, which the Greek won without facing a break point.
But after swapping a pair of breaks, the crucial moment of the decider saw Tsitsipas double-fault to hand his opponent another break at 4-3, and the world No 36 controlled his nerves to serve out and reach the last four.
Basilashvili told atptour.com: “I have played really great matches this tournament. I was not happy with how I played today but I was happy with how I managed my stress levels."
