By Arsenal correspondent Tony Hughes

Gabriel is in a race against time to be fit for Arsenal’s landmark clashes against Barcelona and Manchester United next week.

The centre-back missed the Gunners’ 2-1 win over Leicester on Sunday with what the club said was a minor hamstring injury.

An Arsenal source has told Football Insider that Gabriel is being assessed at the club’s London Colney headquarters to determine the extent of the injury.

The club are hopeful it is not too serious and he will be able to play within weeks, although he is rated doubtful for Saturday’s FA Cup fifth-round clash against Hull at Emirates Stadium.

Arsenal then host Barcelona on Tuesday of next week in the first leg of their last-16 Champions League showdown, before travelling to Manchester United for their next Premier League match five days later.

In other Arsenal injury news, Laurent Koscielny should be back at the weekend after sustaining a dead leg in the first half of the Leicester match, which forced the club into a half-time substitution. The Frenchman was replaced by youngster Calum Chambers at the break.

Kieran Gibbs is also being assessed after turning his ankle in training last week.