Novak Djokovic had a nervy test on Thursday in Cincinnati as he continues his quest for a complete set of Masters titles (gold, gilt-edged, or otherwise). While he was in control in the first set against David Goffin, things rapidly unraveled in the second set. First, a racquet met the force of his displeasure, before Goffin reeled off six games in a row to take the second set and set up a 3-0 lead in the decider.

Grit then kicked in as Djokovic took his own turn at ploughing furrows in the scoreboard, spinning six games of his own on the trot to book a matchup with Stan Wawrinka for the first time since their French Open final.

Needless to say, Djokovic was pretty hard on his assessment of his game. “It's tough to say honestly. It was a solid first set, but whatever happened in the next 45 minutes I don't want to remember it,” he said, smiling. “Credit to him for playing some solid, consistent tennis, always making me play an extra shot. I wasn't on the court. I just lost the intensity and concentration.”

The bubble burst meanwhile for WTA rising star Belinda Bencic, who tearfully exited stage left with a strained right forearm in her third-round match against Lucie Safarova. The teenager has been on an impressive swing since winning her first title in Eastbourne, where she defeated then-world No. 13 Agnieszka Radwanska.

Bencic certainly caught people’s attention last week with that tremendous run, laying waste to a host of Grand Slam champions and finalists left and right. It is a wise head on young shoulders that prevented her from playing through the pain, even though the feeling of retiring for the first time upset her.

She said, “First of all, I don't think it's very serious. I just wasn't 100% today. To beat Lucie or even compete against her, you need to be 100%. I'm really sorry I had to retire. It was I think the first time ever I retired in a match, so it didn't feel very good.”

There was more Serbian drama to come from the ladies with first Jelena Jankovic and then Ana Ivanovic literally clawing their way to wins. In the case of Ivanovic, who was outclassed by a focused Sloane Stephens in the first set, the pair embarked on a marathon eighth game in the second set with 14 deuces and nine break points before Stephens finally held.

“To be honest, I felt like that game helped me a lot because I really struggled to get my rhythm,” Ivanovic said.  “During the match, she was very aggressive. In the second set, I was trying to fight back and trying to change things. The important thing was that after I lost that game, in the next game I managed to stay calm and serve well and actually win that game and go 5-4 up. I really felt like that was the turning point.  Not the eighth game, but the ninth.”

She will face Serena Williams in a rematch of last year’s Cincinnati final.

There was more woe for Rafael Nadal as he came out on the losing end of an encounter with fellow Spanish lefty Feliciano Lopez. His compatriot kept himself in the match by taking the second set, and the crowd were treated to a taut deciding tie-break.

 “I was there during the whole match with the right intensity, with the right attitude, doing the things that I have to do, trying to be more aggressive, trying to go to the net more often,” commented Nadal. “That's what I did. But today I played against an opponent that played a fantastic match, I think. He played the best match he’s ever played against me, without a doubt.”

In the continuing battle around the world No. 2 spot, the incumbent Andy Murray made life hard for himself starting slowly in the first two sets and looking in danger of being outclassed by a speedy Grigor Dimitrov. Only when the Bulgarian’s backhand began to get more ragged did Murray’s tenaciousness keep him in with a shot.

“Playing a three‑hour match of that kind of intensity and the length of some of the points is obviously a good test,” Murray acknowledged. “You want to build up that sort of a reputation that when you are behind that you're going to try to come back and you're going to fight all the way. You know, if that's in the back of your opponent's mind going to a competition that helps.”

The winner of the quickest to the dinner reservation award went to Roger Federer, who sped past the big-serving Kevin Anderson and will face a Spanish leftie in the quarterfinal – just not the one he was expecting. Lopez hasn’t had the better of him since they were juniors but is also enjoying a solid run at the moment.