Novak Djokovic has been struggling with his form this year after losing the world number one spot to Andy Murray at the tail-end of 2016.
Due to the dip in form, the Serbian made a drastic decision to axe his whole backroom staff, and replace his coach with tennis legend Andre Agassi.
Djokovic would have been hoping that having Agassi on side would help him re-find some form and win yet another Grand Slam.
However, their first Grand Slam venture together has ended today as Djokovic has been knocked out by Dominic Thiem of Austria in straight sets.
Not only that, but the Serb was 'bagelled' in the final set, losing 6-0.
The often outspoken John McEnroe, never one to mince his words, has been critical of the star during his game against Thiem, claiming that he's simply missing shots that he shouldn't and wasn't this time last year.
McEnroe has described the poor form of Djokovic as a "lack of confidence" and seems bemused by the situation the Serbian star finds himself in right now.
During the tie break of the first set of his quarter-final against Thiem, Djokovic completely miscues a relatively straightforward two-handed forehand return, hitting it straight out of play.
There wasn't any venom in Thiem's initial shot and it was something that Djokovic should have easily coped with.
There does look to be a lack of confidence in Djokovic's game this year. Mistakes in tennis are part and parcel of the game, but for someone who was world number one as recently as late last year, these are schoolboy errors that shouldn't be happening.
McEnroe says that the awful return during the first set tie-break is testament to why people are asking what's up with Djokovic this year.
"That's why people are saying 'what's going on with Novak Djokovic?' - you didn't see him missing those shots the last few years.
“I’ve watched Djokovic for a dozen years and I don’t recall him missing as many two-handers… relatively easy ones."
Watching the video below, you'll understand exactly what McEnroe is on about - it does appear to be an incredibly easy shot that he messed up, helping no end in handing Thiem the opening set.
McEnroe's comments carried on into the second set, which started with Djokovic pegging Thiem back to some extent.
However, Dojokovic eventually went on to lose the second set.
Do you think Djokovic's confidence looks shot? What's been going wrong with his game this year? Sound off in the comments.
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