The Wigan man fell awkwardly as the two players came together in the 32nd minute of Liverpool's 3-0 win at Anfield on Saturday, with manager Roberto Martinez confirming after the match the nature of the injury.

"To Ben Watson I didn't realise it was serious as that ill (sic) be praying for a speedy recovery mate ill (sic) have you in my prayers every day #sorry," an apologetic Sterling tweeted.

Martinez accepted that the Liverpool youngster had meant to harm in the challenge.

"I haven't seen the challenge back but I don't think any of the players were looking at each other," he told reporters.

"Both were looking at the ball, it's a real accident. It's a nasty collision."