Former Arsenal striker Thierry Henry believes Arsene Wenger should not have played Alexis Sanchez against Norwich after the forward suffered a hamstring injury at Carrow Road.

Sanchez was a doubt going into the game, with Wenger considering resting the Chilean, who had a "little hamstring alarm," with their must-win Champions League game at Olympiakos next week.

But he pulled up an hour into the 1-1 draw and had to be replaced by Joel Campbell. The Gunners now face an anxious wait to discover the extent of the damage.

Wenger insisted after the game that Sanchez had told him he was fit to play, but Henry believes the manager should have rested him anyway.

Henry, who has a role developing youth-level forwards at Arsenal, told Sky Sports: "I can feel for Arsene, in a way, you're playing for the title, you're coming here, you need to win; obviously if you ask Alexis Sanchez if he's OK he's going to say 'yes.' If not, if the guy says 'no,' then he might as well leave the club, you're there to play.

"But I think you almost don't have to ask him anything if you want to rest him. I personally wouldn't have liked that when I was a player but then you take it on the chin and you see the bigger picture because you want to be out there and play for the whole season.

"He plays for Chile, travels 14 hours there and back, he plays every game but even when the game is won sometimes he will still go and put some pressure on teams... I'm not a coach, I don't know how it is with all the pressure of players -- I know I was a pain in the neck when you take me out in the game -- but I thought at the time, the game was won against Dinamo Zagreb; he scored, he had a good game, he didn't get injured, 20 minutes to go, take him out.

"But I'm not a coach. I don't know how the guy would have taken that in the dressing room. At the end of the day it's your decision.

"Now we can all say the same thing. If he played today and he scored he would have said, 'I was right to play him,' but he got an injury so we are obviously going to say he should have rested him."

Sanchez played the whole 90 minutes against Dinamo, even though the game was won with 20 minutes to go after he scored his second to put the Gunners 3-0 up.

And Henry believes Arsenal are showing signs of fatigue.

Alexis Sanchez limps off against Norwich City. Adam Davy / PA Wire/Press Association Images

"I thought Arsenal died, physically, at one point," he added. "I think at the beginning of the second half, Arsenal dropped. To have Robbie Brady at the end of the game saying that he believed that they should have won, that speaks volumes to me.

"And I won't disagree with that. I think, in the second half it looked like they were going to score, and not so much Arsenal.

"Yes, Arsenal had the possession as you expect, they passed the ball around the box, crosses, but in all fairness they only had three shots on target and that was all, in the game. I thought that they didn't look fresh enough in the second half."

Wenger agreed, saying: "I think we were a bit jaded physically, and we had to dig deep to get our game going... in the second half we tried and had a lot possession but you could see that the penetration in the final third was not sharp enough, not incisive enough."

Laurent Koscielny also went off injured early in the game with a hip injury, while Santi Cazorla "finished on one leg" with a knee problem. One positive from the game was the return of Alex Oxlade-Chamberlain after a month out.