Tennis' damning verdict against Djokovic claim

Former tennis player Sam Groth has joined the chorus of doubters who believe Novak Djokovic overstated his injury status during the tournament.

Djokovic last night overcame a sluggish start to defeat German world No.7 Alexander Zverev, 6-7(6), 6-2, 6-4, 7-6(6).

The Serb's mystery injury around his midsection has been a source of contention at the Australian Open. Asked last Friday straight after his third-round win about being ready for his next match, Djokovic replied: "I know it's a tear, definitely, of the muscle. … I don't know if I'm going to step out onto the court or not."

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The top ranked men's player on Sunday even admitted he would've retired from the tournament had it not been a Grand Slam event.

Since revealing the potential seriousness of the injury, Djokovic has been pushed to five sets once and four sets twice on his way to a semi-final berth.

For years the world No.1 has been accused of playing up injury and using it as a distraction when he's in trouble during a match.

Groth, who reached a top ranking of 53 in singles and 24 in doubles, joined a growing list of coaches, rival players and pundits who doubt the severity of the injury.

"Is he injured? I don't know," Groth told Nine.

"If he is, it's not hindering him because he won in five against Fritz with the injury, he beat Zverev, an amazing opponent and I thought it was going to be a tough match and it turned out to be.

"You don't play those kind of physical encounters and get through them like he is if the injury is hampering you to a point where you can't play.

"I'm not saying he's not injured but it can't be that bad if you're able to go five sets, four sets, four sets."

Groth pointed to other players during this year's Australian Open, most notably Grigor Dimitrov who went down to a massive underdog, Djokovic's next opponent Aslan Karatsev.

"We've seen Casper Ruud pull out, Berrettini as well; Dimitrov struggled through a side strain," Groth said.

"Five sets is a true test of the physicality, the mental, the tactical. At the moment Novak says he's got an injury but seems to be pulling up just fine over five sets."

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