Novak Djokovic wrote a heartfelt message to Alexander Zverev on Instagram after his injury retirement in the Australian Open.

Novak Djokovic vs Alexander Zverev, Australian Open Highlights: The first set went on for more than an hour and Djokovic was looking quite good but he shockingly retired as soon as he lost the first set tie-break.

Novak Djokovic will take on Alexander Zverev in the Australian Open semifinals on Thursday, January 23.Djokovic earned a four-set victory over Carlos Alcaraz (4-6, 6-4, 6-3, 6-4) in the

Alexander Zverev urges fans not to boo Novak Djokovic, who retired in the Australian Open Semifinals due to injury

Novak Djokovic has retired from his Australian Open semifinal against Alexander Zverev after losing the first set in a tiebreak. Djokovic missed a regulation putaway volley on top of the net down 5-6,

Alexander Zverev had a classy response to Novak Djokovic's medical retirement on Friday. Zverev won the first set of his semifinal match against Djokovic

Novak Djokovic is out of the Australian Open in stunning fashion. The 24-time slam champion medically retired immediately after dropping the first set of his semifinal match against No. 2 Alexander Zverev in a tiebreak 7-6 (5).

Alexander Zverev recently reached the Australian Open final after Novak Djokovic retired from their semi-final clash but the German still lost to Jannik Sinner