The big-serving Croat has irritated tennis supporters at SW19 with the way he bounces the ball close to 20 times before he serves.
They slammed Cilic for doing it in the win over Sam Querrey in the semi and are venting their fury again today.
Cilic is currently taking on Roger Federer on Centre Court in the final.
One fumed on Twitter: "Please someone at Wimbledon stop Cilic from over bouncing balls before a serve!! This is gunna drive me nuts!!!"
Fans were angry with Marin Cilic taking his time when serving Wimbledon winners through the years Sun, July 16, 2017
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2017 – Garbine Muguruza
Another wrote: "This will be Federers longest match just because of how f**king long Cilic takes bouncing the ball before he serves #hurryup."
Another agreed and tweeted: "Not a good sign for Cilic that he took 382 bounces before his opening serve… #WimbledonFinal."
While a fellow tennis added: "Cilic bouncing the ball a billion times before each serve is going to very quickly get very annoying. #Wimbledon."
Federer is bidding to win a record eighth Wimbledon title today at the age of 35.
He was given a rapturous reception as he walked on to Centre Court and he had fans there – and at home – on his side.
Other fans wrote on Twitter: "How many times does Cilic have to bounce the ball before he serves?"
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Another sarcastically said: "Cilic should bounce the ball a bit more before he serves."