Danny Welbeck is facing Euro 2016 heartbreak after suffering another injury blow.
The Arsenal and England striker injured a knee in a first-half challenge with Manchester City's Bacary Sagna and was unable to carry on.
Gunners boss Arsene Wenger revealed Welbeck was "very down", suggesting the 25-year-old knows he faces a lengthy lay-off.
If scans show a tear in his knee, the former Manchester United forward will face several months out of action and miss this summer's finals in France.
Wenger said: "We have to wait for a scan. I hope it's not bad news. Let's wait until we have a real diagnosis.
"At half-time, I looked at him, he was very down and he had pain. Good news is that he will not be out for the Euros and bad news is that he will be."
Asked for his gut feeling on whether Welbeck would be fit in time, Wenger said: "I'm an optimist."
Welbeck only returned in February from a 10-month spell out with a problem on his other knee.
Wenger has admitted that he is "a bit worried", after Welbeck was substituted in the first-half of the 2-2 draw at Manchester City .
The England striker went down holding his right knee after 20 minutes when he collided with Bacaray Sagna and blocked the ball.
After receiving treatment on the sideline, Welbeck was substituted for Jack Wilshere and limped down the tunnel.
The former Manchester United forward has battled a series of injury problems over the past year and Wenger admitted the initial prognosis is not good.
"The first signs look like lateral meniscus," said the Arsenal boss following the game.
Gallery: City 2-2 Arsenal
Read more: Euro 2016 Squads
"He looks down, and he's not a guy who likes to go off. I'm a bit worried.
"I don't want to say about the Euros - let's be a bit more optimistic.
“At half-time I looked at him, he was very down and he had pain. Good news is that he will not be out for the Euros and bad news is that he will be."
Welbeck will undergo a scan today where Arsenal hope to learn the extent of the injury.
The 25-year-old looks near certain to miss Arsenal's final game of the season, when the Gunners host Aston Villa needing a point to ensure they seal a place in next season's Champions League.
Welbeck's latest injury setback is a bitter blow to the forward, who only returned in February from a 10-month spell out with a problem with his other knee.
Worryingly for Welbeck, Roy Hodgson will announce his England squad for Euro 2016 on Thursday morning.
More encouraging for Arsenal, Wilshere replaced Welbeck in the 23rd minute, as he looks to nail down a place in Hodgson's squad for France.
"I feel good," he told the BBC after the game. "That was just what I needed, a game of that intensity with the pressure.
"This season has been disappointing for us - we wanted to win the league. If we can get third in the league we'll be delighted.
"I don’t want the season to end - I’m just getting started, I feel fresh, hopefully I can get more minutes next week and then we’ll see what happens."
Wenger also admitted that Wilshere's injury has impacted their season.
"Jack Wilshere had three games with the reserves and though he finished tired he played well," said Wenger.
"It's difficult to measure how much we have missed him this season because of course you want your best players available so you can rotate. If you have injuries you cannot do that."
Wenger praised the character of his Arsenal side for twice coming from behind to secure a point that has taken them a step closer to securing a top-four spot.
A point for Arsenal at home to relegated Aston Villa on Sunday will be enough to secure third spot, but Wenger's men can finish second if they win and Tottenham lose at Newcastle.
“It's in our hands and we have seen again that we just want to finish the job,” said Wenger.
“We have to keep the focus. Our character has been questioned a few times this season and we gave the right response, which was on the pitch.
“If you look at the top four teams, we have the best results against them, so that doesn't come without character.
“When we were down in the game we showed character and came back twice.”