Arsène Wenger described Thierry Henry's match-winning return to Arsenal as the stuff of dreams after the French forward, on his first appearance for the club in almost five years, scored with his fifth touch to propel his side into the FA Cup's fourth round.

Henry, who has re‑signed on loan from New York Red Bulls for what is likely to prove an eight-week stint, was introduced into the fray 22 minutes from time with this game goalless and edging towards a replay. Nine minutes later, supplied by Alex Song, the 34-year-old duly registered his 227th goal for Arsenal and extended his club‑record tally to leave his manager pinching himself in victory.

"It was a dream, a story you'd tell a young kid," said Wenger. "Unfortunately it's not often like that in our game but sometimes it happens. He's done it all. You could see straight away that he had a presence on the pitch and, if we could find him, he'd be dangerous.

"He's sharp, physically. I'd seen that in training and I wouldn't have used him if he wasn't ready. But he was already a legend here. Now he's added just a bit more to the whole story.

"He feels some pressure still. He's a proud guy and doesn't want to disappoint people. That's what champions are all about. He knows he'll be compared to what he did before and he wants to be seen as someone who always does well. It's a kind of combat and you want that to be a success as a player. But he remains a special player."

Henry departed with the sponsors' man‑of‑the‑match award, which he was baffled to accept, having carried the vote even while he remained an unused substitute. The Leeds manager, Simon Grayson, had claimed the striker's impact had been "written in the stars".

"It's all kind of weird," Henry said. "When I came back from holiday in Mexico, 15 days ago, I never thought I'd play for Arsenal again, let alone score the winner. I don't know what to say, to be honest. The feeling I had when I scored was amazing.

"I am enjoying the club as a fan where I wasn't before: now I know how people feel when they score for the club they support. But it wasn't the plan [to end up as the hero]. I will always remember tonight. I don't know why but, when it comes to Arsenal, something happens with me. Sometimes in a bad way but most of the way in history in a good way."

The winner here was his 12th goal in as many games against Leeds and his first for Arsenal at the Emirates Stadium since a header helped defeat Manchester United in January 2007. The impact made, with Robin van Persie rested and Marouane Chamakh about to join Gervinho in departing for the Africa Cup of Nations, prompted immediate questions over whether the loan agreement with the Red Bulls could be extended until the end of the domestic campaign. "He has six and a half weeks with us and we have not envisaged more," Wenger said. "We can go to eight weeks but not longer."

The stay already includes a match against Manchester United here and an extension would culminate in the north London derby with Tottenham Hotspur at the end of February, which seems an apt occasion on which to bow out for a second time. "I was happy to get him back," Wenger said. "He's a guy who's very focused, intelligent and planned with his career.

"In his head it was always Barcelona [after Arsenal], then the States. That's what he did. What is good for the club, and for the young players, is this is a guy who has done it all but still prepares 100%, is focused and motivated and comes on with an immense desire to do well.

"When he was in this position to score, I thought: 'Oh, that's your angle but it's a bit too close.' That's where he surprised me. He didn't force the shot and still made it look easy. I thought he was a bit too far to the left to pull it off but he always had that special finishing. That was Thierry Henry finishing."

Asked whether there was any coincidence that Henry and Paul Scholes at Manchester United are making eye-catching returns this month, Wenger said: "It looks like the best transfer market is to get your old players back. He can play together with Robin [van Persie, who will return against Swansea City on Sunday]. They did play together before, after all."