Chelsea defender Antonio Rudiger took to Twitter on Monday night to congratulate Alexander Zverev, after the German tennis player beat world number one Rafael Nadal at the ATP Finals.Rudiger has had an injury-ravaged campaign at Stamford Bridge this term after missing the start of the season following knee surgery in the summer, and later tweaking his groin against Wolverhampton Wanderers in September.The crocked 26-year-old was expected to make his comeback against Crystal Palace at the weekend, but aggravated the issue and was forced to undergo surgery last Tuesday. He is now expected back at the end of November, as his injury woes finally look to be nearing their end.Watch Chelsea Videos With StreamFootball.tv Below

He is seemingly enjoying his time out on the sidelines, though, as Rudiger headed to The O2 Arena on Monday to watch on as his compatriot overcame Nadal 6-2, 6-4 to record his first win over the Spaniard in six attempts.

Zverev emerged triumphant after an hour and 24 minutes of play, where the German's serve was faultless and his forehand shots were thrashed down the court.

And after Zverev hit the match-winner, he met up with Rudiger to exchange a signed racket for the defender's signed Chelsea shirt, at which point the Blues man sought to congratulate his compatriot on the win.

Rudiger shared the moment on Twitter, too…