Paris: Japanese tennis star Kei Nishikori fought back in a marathon four-hour match to beat Russian 23rd seed Karen Khachanov 4-6, 6-2, 2-6, 6-4, 6-4 and secure a place in the French Open third round.
Three days after another five-set comeback over Italian Alessandro Giannessi, world No.49 Nishikori -- ranked fourth in the world during his peak -- refused to give up and set up a clash with Switzerland's Henri Laaksonen.
Laaksonen, the world No. 150, held his nerve to defeat 11th seed, Spain's Roberto Bautista Agut, 6-3, 2-6, 6-3, 6-2 in two hours, 21 minutes.
Laaksonen, 29, struck 53 winners, including nine aces, in his first top 20 win of his career.
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World No.5 Stefanos Tsitsipas of Greece breezed into the third round following a 6-3, 6-4, 6-3 win over Spaniard Pedro Martinez. He will take on American world No. 34 John Isner in the third round after the latter eased past Serbia's Filip Krajinovic 7-6(6), 6-1, 7-6(5).
Sixth seed Alexander Zverev of Germany used all his energy to overcome Russian qualifier Roman Safiullin 7-6(4), 6-3, 7-6(1) to secure a spot in the third round.
World No.6 Zverev, who recovered from two sets down against qualifier Oscar Otte of Germany on Sunday, took 60 minutes to win the nerve-wracking opening set against Safiullin.
Zverev will next play Serbian Laslo Djere, who defeated compatriot Miomir Kecmanovic 4-6, 4-6, 6-3, 6-2, 6-3.
Zverev was broken when serving for the set at 6-5, but got off to a strong start in the tie-break to win 7-6(4). This is the fifth time Zverev has progressed to the French Open third round, with his best showing coming in 2018 and 2019 when he reached the quarter-finals.
In the first ever men's night session on Court Philippe-Chatrier late on Tuesday evening, world No.1 Novak Djokovic of Serbia eased into the second round after a 6-2, 6-4, 6-2 win over American 66th ranked player Tennys Sandgren.
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Djokovic will next face a top 100 player from Uruguay, Pablo Cuevas, who advanced after a 6-3, 6-1, 6-3 victory against Frenchman Lucas Pouille.
Djokovic, beaten by world No. 3 Rafael Nadal of Spain at the Roland Garros final last year, has now won his previous 16 first-round matches in Paris.
IANS