Kei Nishikori has said that he is "very disappointed" that a calf injury has forced him to withdraw from this year's Wimbledon tournament.

The fifth seed had been scheduled to play in the second round on Centre Court this afternoon but confirmed shortly before the start of play that he would not be able to take part in the match.

The 25-year-old told the tournament's website: "It got better before the first match last week. I thought it was really going to be okay. But last match in fifth set I was hurting too much.

"I'm very disappointed. Especially [as] it's a Grand Slam. I thought I was playing well on grass. So very unfortunate to lose this chance. But, you know, I try to keep it up. Hopefully I can do well in the US series [this summer].

"I have one month before Washington. So I'm sure it's going to be okay. I need to get another good preparation for the US. I always play good in the US. I like hard courts. So I hope I can have good preparations again. I think the injury should be okay for my next tournaments."

Nishikori reached the fourth round at Wimbledon for the first time in 2014.