Arsene Wenger has ruled Theo Walcott out for the remainder of the season after the midfielder hobbled off the Emirates pitch clutching his hamstring in Arsenal's 0-0 draw with Chelsea on Saturday.
However the Arsenal manager believes Walcott will recover in time for England's assault on Euro 2012.
Wenger said: "It looks like a serious hamstring."
The Gunners boss added: "First we assessed the hamstring, he wanted to go on and stay on the pitch, and I think he should have gone off straight away because the second time it was a real hamstring [injury]. I think now for him it will be tough to come back before the end of the season. It is usually 21 days [minimum]. He should be OK to play for England, but I don't think he will be ready to play for us."
Walcott's injury was an untimely blow for Arsenal, who failed to further cement their place in the top four of the Barclays Premier League. Wenger was quick to lay the blame for the scoreless result at the feet of Chelsea, branding their play negative.
"Before the game, I thought it would be an open one - we had to win, they had to win," he said. "They decided to lock up the game and catch us on the break only, with two wide players who are quick, and Fernando Torres.
"I felt we had a very solid defensive performance. Going forward, we didn't find our quick passing game and the regret we have today is that we played offensively with a handbrake and not as clean technically as we can do."
Wenger, whose side suffered a shock home defeat to Wigan on Monday, added: "That is why we didn't open them up enough. It was a bit similar to what we saw against Wigan and that's a regret I have today."
Wenger reserved praise for captain Robin van Persie, who missed several chances either side of half-time, as he said: "He gave absolutely everything again today. He was unlucky in the first half, he had a free-kick he deflected and it was a clear-cut chance.
"Then, when he was through, I think he rushed his decision-making a bit, when he took it with his right foot, because he had Abou Diaby coming in completely on his own. And he was caught offside one time and I am not sure he was."