Ander Herrera injury: Manchester United midfielder could miss Chelsea match on Sunday

Herrera went off at half-time after aggravating rib injury

(GETTY IMAGES)

Manchester United could miss Sunday's Premier League clash with Chelsea after aggravating the rib injury that had kept him out for a month.

The 25-year-old was substituted at half-time of the 2-2 draw with West Bromwich at The Hawthorns on Monday night, after feeling pain in his rib.

The midfielder broke his rib against West Ham on 27 September and was initially ruled out for six weeks, but made a speedy recovery aided by the use of a specially designed corset.

Herrera is reported to have been assessed on Tuesday morning and is now racing to be fit for the massive game against league leaders Chelsea at Old Trafford.

United also saw record signing Angel Di Maria taken off in the draw; he too is facing a race to be fit in time for the match.