Karen Khachanov grabbed a stunning win from the jaws of defeat as he booked his place in the quarter-finals of the Kremlin Cup in Moscow.
The top seed and defending champion had to save five match-points, but was able to somehow find a way past Philipp Kohlschreiber 3-6, 6-3, 7-6 (7-5).
Khachanov saved three match points to force a final-set tie-break, then saved two more to prevent victory for the German, who was celebrating his 36th birthday.
Khachanov told atptour.com: “I can’t remember the last time I had a comeback like that.
“I had to fight and try to find my game. I am really happy that finally I can go through here in my hometown of Moscow.”
Khachanov, who advanced when Kohlschreiber served his third double-fault, will next face Italy’s Andreas Seppi, who fought back to beat Roberto Carballes Baena 5-7 6-1 6-3.
Also in Moscow, fourth seed Dusan Lajovic beat qualifier Lukas Rosol 4-6 7-6 (6) 6-3, and seventh seed Adrian Mannarino was a 7-6 (4) 6-2 victor over Mikhail Kukushkin.
At the European Open in Antwerp, wild card Stan Wawrinka got the better of Feliciano Lopez to reach the quarter-finals with a 6-7 (4) 6-4 7-6 (4) win.
Wawrinka will next face Gilles Simon, who beat fellow Frenchman Jo-Wilfried Tsonga 6-4 7-5, while fifth seed Guido Pella also reached the last eight with a 7-5 7-5 win over Soonwoo Kwon.
In first-round action, Frances Tiafoe saw off qualifier Yannick Maden 7-6 (7) 6-3, and eighth seed Pablo Cuevas beat Bolivian Hugo Dellien 6-4 6-3.
Dan Evans was knocked out in the second round of the Stockholm Open by Serbian Filip Krajinovic, who out-lasted the new British number one 7-5 2-6 6-3.
Second seed Grigor Dimitrov went out 6-7 (7) 6-3 7-6 (3) to American Sam Querrey, and third seed Taylor Fritz also fell, 7-5 6-4 to Yoshihito Nishioka of Japan.
In the one remaining first-round match, home favourite Mikael Ymer came through 7-5 6-4 against Portugal’s Joao Sousa.
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