Djokovic on left knee: 'I already have troubles with the right one'

Novak Djokovic mustered up some gutsy tennis Friday night to battle his way past #NextGenATP star Jakub Mensik to book his place in a ninth semi-final at the Rolex Shanghai Masters.

However, the scare posed by the 19-year-old, who took the opening set against the record four-time champion, wasn’t the only fright that Djokovic endured in the contest.

“It was a strange feeling [during] those couple of points in that game, but after that it was fine,” said Djokovic, who pulled up holding his left knee in the sixth game of the deciding set. “Hopefully when it cools down I'm not going to have any troubles with it, because I already have troubles with the right knee, so it wouldn't be great. Let's see what tomorrow brings.”

Sealed with an ace ?

The moment @DjokerNole became the third oldest man to reach ATP Masters 1000 semi-final after Federer ?@SH_RolexMasters | #RolexShanghaiMasters pic.twitter.com/glxPE8KpU9

The 37-year-old underwent successful surgery to repair a meniscus tear in his right knee following his withdrawal from the quarter-finals of Roland Garros in June. Djokovic made a miraculous recovery to make it to the Wimbledon final just three weeks later and has been competing with a soft knee brace ever since.

“China has always been a happy place, a place where I really played my best tennis throughout my career,” said Djokovic, who is seeking a record-extending fifth title in Shanghai. “These kinds of matches, against teenagers, are what really motivates me, keeps me going, and pushes me to really dig deep. To show to the world that I still have it in my legs, that I can still go the distance with the young guys.”

After facing two exciting #NextGenATP prospects in Alex Michelsen, whom he defeated 7-6(3), 7-6(9), and Mensik, Djokovic will face seventh seed Taylor Fritz on Saturday for a spot in the championship match. Now into a record 77th ATP Masters 1000 semi-final, the No. 4 in the PIF ATP Rankings feels as if the American will pose a similar threat to what he has already encountered this week in China.

“I was challenged by [Alex] Michelsen in the first round, and today [in] tough matches with big servers, said Djokovic, who edged Mensik 6-7(4), 6-1, 6-4. “I'm going to have a big server opponent tomorrow, Fritz, so I have to be ready for another difficult, tight match.

“[It is] quick conditions, if you serve well it's quite a big advantage. Hopefully I can be fresh, and now we are entering the last four players of the last couple of matches of the tournament. Now is the time for me to really try to step it up even more, and hopefully I can get a chance to be in the finals.”

After coming through in four sets at this year’s Australian Open quarter-final, Djokovic improved to 9-0 in his Lexus ATP Head2Head series with Fritz, though he will not rest on his laurels after seeing the explosive 26-year-old reach his maiden Grand Slam final at last month’s US Open.

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