Arsenal manager Arsene Wenger was hopeful captain Cesc Fabregas had not done too much damage in suffering a hamstring injury after scoring twice in the Gunners' 3-0 win over Aston Villa.
Sunday's success at their Emirates Stadium home saw Arsenal move to within four points of Premier League leaders and London rivals Chelsea.
But victory against a Villa side who stayed fourth in the table was anything but assured until the 57th-minute introduction of Spain midfielder Fabregas.
The skipper struck a superb curling shot from a 25-yard free-kick he himself had won to put Arsenal 1-0 in front in the 65th minute and then made sure his team collected all three points by finishing a sweeping move nine minutes from time.
But in the process of scoring that second goal, Fabregas suffered a recurrence of his hamstring injury and soon afterwards his decisive 28-minute spell on the field was over, although Arsenal still managed a third goal in stoppage time through Abou Diaby.
"It's a recurrence of his hamstring," Wenger told Sky Sports. "We knew before the game it was not perfect. We will see if we have long regrets or short regrets. I don't believe it's too bad, he doesn't think it's too bad."
Wenger added: "If it's a pull again it's three weeks (out) so we hope it is only a scar."
The Frenchman refused to say if Arsenal would have won had Fabregas stayed on the bench. "That's very difficult to predict. I believe we were dominant. I believe in the last 20 minutes we could have made the difference (to win the game)."