World No.1 Novak Djokovic admitted that his knee troubled him during his marathon win of 6-1, 5-7, 3-6, 7-5, 6-3 against Argentina’s Francisco Cerundolo on Monday. This was the Serbian’s 370th win at the Grand Slam, as he leapfrogged Roger Federer’s tally of 369 and now has most wins at the all the Majors combined.

The talisman had to battle against Lorenzo Musetti in a five-set marathon in the third round and once again had to dig deep against Cerundolo. In fact, the Argentine was leading by 4-2 in the fourth set after winning two of the first three sets. However, Djokovic was able to get his break back. 

Cerundolo also had a break point opportunity at 30-40 (5-5) in the fourth set but could not grab it.

“Again a big, big, big thank you because once again like the last match, the win is your win,” Djokovic told the crowd in his on-court interview.

Djokovic said he was troubled by his knee pain during the match.

“I started feeling the pain [in set two] and asked for the physio treatment and the medical timeout and tried to take care of it,” he said. “It did disrupt me definitely in play. For two sets, two sets and a half, I didn’t want to stay in the rally too long. Every time he would make sudden drop shots or change directions, I would not be feeling comfortable to do the running.

“At one point I didn’t know, to be honest, whether I should continue or not with what’s happening.”

Djokovic feels he is in a good physical state despite playing two marathon matches.

“I didn’t feel that the last match has affected me so much that I’m unable to run or to sustain the level I played for over four-and-a-half hours,” he explained. “It was longer than the match against Musetti. So physically I’m OK. Thankfully I was able to recover quickly.”

Novak will face 2022 finalist Casper Ruud in the quarterfinals on Wednesday.