French Open 2018: Alexander Zverev beats Karen Khachanov in five sets
|French Open 2018|
|Venue: Roland Garros, Paris Dates: 27 May-10 June|
|Coverage: Daily live radio and text commentaries on BBC Radio 5 live, the BBC Sport website and app.|
Second seed Alexander Zverev came through a third successive five-set match to see off Karen Khachanov and reach the French Open quarter-finals.
German Zverev, 21, beat the unseeded Russian 4-6 7-6 (7-4) 2-6 6-3 6-3 in three hours 29 minutes in an enthralling match in Paris.
It is the first time Zverev has reached the last eight of a Grand Slam.
He will play Austrian seventh seed Dominic Thiem, who beat Japan's Kei Nishikori 6-2 6-0 5-7 6-4.
Thiem, a semi-finalist at Roland Garros for the past two years, has won eight of his 10 ATP titles on clay and dominated on his favoured surface.
Japan's Nishikori made his only break point of the match count to take the third set before Thiem regained control, breaking in the seventh game of the fourth set and sealing victory when Nishikori sent a forehand long.
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Zverev has climbed to number three in the world rankings despite never previously having gone beyond the fourth round of a Grand Slam, achieved at Wimbledon last year.
At 6ft 6in, he has been touted as a future world number one, but glimpses of his potential were interspersed with a failure to close out vital points and a hint of fatigue.
Khachanov, 22, is another player with a bright future and looks particularly dangerous on clay.
But Zverev fought back from 2-1 down to win the final two sets and become the youngest quarter-finalist in Paris since a 20-year-old Juan Martin del Potro in 2009.
"I'm young, so I might as well stay on court and practise a little bit," said Zverev. "It's the best, a five-set match.
"I've been down 2-1 every single time but I'm unbelievably happy to be into the quarter-finals. All the hours in the gym have paid off."
With 20-time major champion Roger Federer opting to sit out Roland Garros, Zverev is seen as the most likely challenger to world number one and 10-time champion Rafael Nadal for the title.
"I'm top three in the world now," he added. "Other young guys are coming up strong - in the end we'll be very high soon.
"With time we will see who can become the next Grand Slam champion, who can become the next world number one.
"Right now Roger and Rafa are dominating, but we are doing everything we can to change that."
Another mammoth battle for Zverev
Zverev was taken to five sets by Dusan Lajovic in the second round and saved match point against Damir Dzumhur in the third round.
He enjoyed the perfect start on Court Suzanne Lenglen with a break of serve, but Khachanov hit back immediately and Zverev tossed his racquet in frustration at being asked to replay the point by a line judge after staving off two set points.
It was a brief reprieve as Khachanov's aggressive volleying tactics earned him a third set-point chance and this time the Russian took it to clinch the opener.
Zverev roared in celebration at making a breakthrough halfway through the second but, serving to draw level in the match, wasted three set points before eventually winning it on a tie-break.
World number 38 Khachanov accelerated away with the third set, earning a double break after Zverev missed a chance to hit back.
But Zverev edged a tense fourth set in which he was issued a code violation for being coached from the stands by his father Alexander Sr.
Zverev's class and persistence shone through in the final set as he took an early break and converted match point on Khachanov's serve.
Thiem predicts 'legendary' quarter-final
Zverev's quarter-final opponent Thiem is the last man to beat tournament favourite Nadal on clay, defeating him in straight sets in the last eight of the Madrid Open to end the Spaniard's run of winning 50 consecutive sets on the surface.
But the 24-year-old was then beaten in straight sets by Zverev in the final, and expects another tough match against the German.
"It's the match, especially in Germany and Austria, everybody was hoping for," said Thiem. "So I think we can make it legendary and that would be very nice.
"It's going to be a very tough match against him. He's going to be pumped. It's his first quarter-finals. He wants to move on, for sure. So I hope I'm a little bit more experienced in this one."
Thiem is also keen to improve on his two French Open semi-finals in 2016 and 2017 this year.
"I think for me it's time to move on to make a great step, because I'm turning 25," he added. "I'm not that young anymore. That's his part. He's only 21."