Chelsea captain Gary Cahill has apologised to Per Mertesacker after the Arsenal defender was left needing stitches following an aerial clash between the pair.

Cahill caught Mertesacker in the face during the first half of Sunday's Community Shield at Wembley, an incident which left the Gunners veteran bloody and needing to be replaced by Sead Kolasinac.

Arsenal confirmed Cahill had entered their dressing room to say sorry to the former Germany international after the match, which Arsene Wenger's men won 4-1 in penalties after a 1-1 draw.

Mertesacker hailed his opponent for the gesture and revealed he was feeling surprisingly good despite the head injury.

"It is great sportsmanship from him," Mertesacker told Arsenal Player of Cahill's apology.

"He is as well a champion, a decent fella, so I thanked him again for coming and taking care of that, it is an accident, but it was a nice touch.

"I'm pretty well for that hit and for the deep cut I suffered, I feel quite well.

"The result I think gives me a lift right now. I can remember everything [about the clash], so I think there's no concussion, it was just a very, very deep cut and the doctors already said on the pitch they didn't want to take any risk, so took me off as a precaution and I got some nice stitches."

Mertesacker is unsure whether he will be fit in time for the first game of the Premier League season, with Arsenal hosting Leicester City on Friday.

"I'm not quite sure yet," he said. 

"We need to take care of this - you know how the swelling goes and if it turns into a black eye or something. It is too early to say because health is the first thing."