Substitute Aaron Ramsey had cancelled out James McClean’s second-half opener before Henry turned in Andrey Arshavin’s teasing cross in the 90th minute to hand the Gunners a crucial victory at the Stadium of Light.
“He finished the story of the legend today in the championship,” said Wenger, who admitted his disappointment at not being able to extend the striker’s loan deal. “I hope he will add some in the Champions League on Wednesday now.
“Certainly he got us the three points in a difficult game where Sunderland were resilient, well organised and tried to catch us on the break every time.
“You could see that they have a lot of spirit in their side. It was also on a very difficult pitch. We had a lot of the ball but we couldn’t create a lot because our passing was good but it was very difficult to get into their defence.
“It might haunt me again because then people will say ‘why did he not stay?’
“It just shows you as well that these players never lose it. Exceptional talent survives. You have that with Giggs and Scholes at Manchester United and Thierry here. It is just a luxury to have a player like him on the bench.”
Wenger’s men fell behind in the 70th minute when Per Mertersacker collapsed in agony while in possession, allowing McClean to race through on goal and smash his effort past Wojciech Szczesny.
And the Arsenal boss admitted his concern at what looks to be a serious ankle injury to the Germany international.
“Mertesacker told me that he got a shot in his ankle and couldn’t move at all anymore,” Wenger added. “We are a bit worried about his ankle I must say because he goes home on crutches. He has done some ligament damage, but how big that is we will have to check tomorrow. For sure he is out for Wednesday.”
But Wenger felt McClean was right to play on when Mertersacker went down. “I thought about [the possibility of stopping play] during the game after they scored but you cannot demand that. You do not know if a guy has gone down through injury or because he slipped. It’s just that in the action you cannot demand to stop.”
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