Daniil Medvedev overcame a wobble to beat a fighting Tommy Paul on Friday and reach the semifinals of the Shanghai Masters, setting up a showdown with rising star Rafael Jodar.
At age 20, the Spaniard is the youngest player to reach the Shanghai semifinals since the tournament's inaugural edition in 2009.
Medvedev, the 2019 Shanghai champion, overcame inconsistent serving to beat Paul 6-3, 1-6, 6-3.
The 30-year-old saved seven break points to hold back the American in a marathon sixth game, giving little away as he broke to take the first set when Paul fired long.
But the 18th-ranked Paul returned inspired in the second set, displaying fantastic defence as Medvedev drove him around the court.
He was rewarded when Medvedev double-faulted twice in a must-win game to tumble into a decider.
The Russian, ranked sixth, cruised to a 2-0 lead in the third set and carried that momentum to the end, breaking again to win on his second match point.
Earlier, 13th-ranked Jodar beat Norway's Casper Ruud 4-6, 6-4, 6-3 – recovering from a set down for the fourth time in a row this week.
Both players were tested but held serve to start with until Ruud capitalised on a break point, taking the first set with a searing forehand into the corner.
But Jodar's brilliance shone through, dazzling the crowd with a gorgeous over-the-shoulder smash in the fourth game of the second set.
Despite losing that game, the Spaniard held his nerve and won a crucial break point to go up 5-4 before closing out the set at the first time of asking.
Ruud, ranked 24th, saved three match points in the third set but double-faulted to hand Jodar victory.
"Casper is a very tough player," Jodar said afterwards. "I had to give my best level today to win this match."
Top seed Alexander Zverev faces Alejandro Davidovich Fokina in the other semifinal on Saturday.