Cesc Fabregas is a doubt for Arsenal's Champions League last 16
second leg against Porto.
Fabregas opened the scoring in the Gunners' 3-1 win over
Burnley on Saturday but had to be substituted shortly afterwards.
Arsenal boss Arsene Wenger: "He has a hamstring problem and
how big the damage is we don't know yet because it's too early.
"We have to make a late decision over whether he plays on
Tuesday, certainly. It is the same hamstring [he hurt earlier in
the season]."
Arsenal must overturn at 2-1 deficit from the first leg
against the Portuguese side.
Wenger also hailed the performance of Theo Walcott.
The winger came in for criticism after his performance for
England in midweek, but responded with an impressive display and
the crucial second goal to put Arsenal back in front after David
Nugent's equaliser.
Wenger said: "Theo Walcott gave you the great response you
waited for.
"He does what a player has to do - not talk in the newspapers
and let your performance talk on the pitch.
"He didn't answer any critics other than with a good
performance today and that's what you want from a player. That
shows he is mentally strong.
"I was quite sure he would respond with a good performance
but you never know, it affects you when you get criticised. The way
he answered that at his age is remarkable."
