Dialed-in Daniil Medvedev suppressed a late surge from Frances Tiafoe to beat the American 7-5, 7-6 (7/4) and reach the Indian Wells final for the first time.
Sixth-ranked Medvedev, coming off ATP titles in Rotterdam, Doha and Dubai in the space of three weeks, pushed his win streak to 19 matches and awaits the winner of the other semifinal between top-seeded Spaniard Carlos Alcaraz and 13th-ranked Italian Jannik Sinner.
Alcaraz, 19, and 21-year-old Sinner are 2-2 in four prior meetings, but it was Alcaraz who came out on top in their most dramatic clash – a five-set US Open quarterfinal that lasted five hours and 15 minutes, its 2:50am finish the latest in US Open history.
Alcaraz would go on to lift the trophy and become the youngest world No 1 in the history of the rankings.
Medvedev, who had never before made it past the fourth round in the combined WTA and ATP Masters 1000 event in the California desert, was in firm control for much of the one-hour, 46-minute contest.
But he needed eight match points to put away 16th-ranked Tiafoe, finally securing victory with his ninth ace of the day.
“It was crazy at the end,” Medvedev said. “I got super tight. I would say that (after) 6-5, 40-0, I think I got tight at deuce when I was like, ‘Oh my God, that’s a lot of opportunities missed. This could go not well for me.’
“The ace was a relief,” he added. “I’m just really happy that I managed not to lose this match.”
Medvedev, showing no sign of trouble from the right ankle he twisted in a fourth-round win over Alexander Zverev, was patience personified as he wore down Tiafoe in the first set.
Tiafoe had reached his first Masters 1000 semifinal without dropping a set, but Medvedev stymied his every attempt to break through his serve, winning 24 of his 27 service points in the opening frame.
In a match of metronomic rallies, Tiafoe was first to blink, falling behind 0-40 in the fifth game, only to roar back with five straight points to hold.
But Medvedev broke through suddenly in the 11th game, another backhand into the net from Tiafoe giving him a break point that Medvedev converted with a net-skimming forehand to end another rally.
Break in hand, he pocketed the set with a love game.
Medvedev quickly gained the edge in the second, breaking Tiafoe in the opening game with a forehand winner that curled back inside the sideline as it dropped.