Talk is cheap.

Jack Sock's words proved expensive.

Nadal: Disrespect At Root Of Rift With Bernardes

Sock was hit with a $5,000 fine for unsportsmanlike conduct at Wimbledon.

Squandering a two set lead, Sock fell in five sets to Matteo Berrettini in his Wimbledon opener.

An angry Sock informed the Italian "Your coach is a piece of shit, by the way," during the post-match handshake.

Sock was fined for that outburst and while he admitted he was wrong, the 18th-seeded American also accused Berrettini's coach of verbally goading him.

"He was in the wrong for saying the things he did," Sock said in comments published by the Associated Press. "I'm definitely in the wrong for saying what I did after the match. I shouldn't have gone that far."

It's been a horrific season for Sock, who suffered his fifth straight opening-round loss as his record dropped to 5-13. Sock hasn't won a singles match since defeating David Ferrer in the opening-round of Rome last month, including a winless skid through grass-court season.

The explosive American won his first career Masters title in Paris last fall and powered into the semifinals of the year-end Nitto ATP Finals in London, but he's looked lost on court this season.

"Jack Sock, he hasn't been playing with any confidence for a while," ESPN analyst John McEnroe said in a conference call to promote the network's Wimbledon coverage. "I'm not quite sure what's happened with him. But considering I think he thinks grass is his least favorite surface, even though I think he could play on grass and do well, I haven't seen any indication from him that he believes he has much of a shot either at this point."

Sock, who partnered Vasek Pospisil to beat the Bryan brothers and win the 2014 Wimbledon doubles crown, is partnering Mike Bryan this week. The seventh-seeded American team has advanced to the third round.

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