Call him the comeback king. Down two sets to love against Jannik Skinner with a berth to the Wimbledon semifinals on the line, world no. 3 Novak Djokovic dug deep, winning the next three sets to advance to his 11th career Wimbledon semifinal, tying him with Jimmy Connors for second all-time. The win also extended a crazy Djokovic record in five-set matches at the Grand Slams. ESPN Stats and Info has the details.

That's incredible. Djokovic's win at Wimbledon was the 34th 5-set match he has won in his career at the four Grand Slams combined, which is the most in tennis history. In other words, don't sit back if you get a lead against Djokovic in any major.

For a player who struggled with injury and fitness earlier in his career, it's a testament to the hard work Djokovic has put in that he is now tennis' Iron Man in five set matches.

In 5-setters in general, Djokovic owns a 37-10 record, with the 37 wins trailing only Ilie Nastase in the Open Era, via ATP Media Info. Just remarkable.

If that doesn't capture just how hard it is to beat this guy, maybe this clip will.

Unreal. Djokovic went full extension, going into a split to hit that passing shot for a winner as a stunned Jannik Skinner and Wimbledon crowd looked on. It really is tennis from another planet, as Tennis TV so aptly put it.

Not only does Djokovic have the mental fortitude to outlast opponents in 5-setters, but he can physically do crazy things like that.

No wonder Novak Djokovic is one of the greats.