Arsène Wenger believes Jack Wilshere is "coming back to his best" after the midfielder scored Arsenal's first and set up their second in a 2-1 win over Aston Villa that lifted the London club back to the Premier League summit.

The goal was Wilshere's fifth of the season and capped an impressive performance from the England international on a night when Arsenal looked to be coasting to a comfortable victory until Christian Benteke scored 14 minutes from time.

Arsenal held on for a fifth successive win in all competitions to leapfrog Manchester City. "It was a big win for us tonight," Wenger said. "There were two very different halves. The first half was about us playing our game – the speed of our passing and control of the game – and the second was more about fighting. It was down to a different style from Villa, who played a more direct game, and we were maybe a bit cautious to try and keep the 2-0. We kept fighting and our defenders kept us in the game. It was a nervous finish and we had to fight until the end."

The pressure was on Arsenal after the other six teams in the top seven had won at the weekend. "You're always under a bit more pressure when you play last as you know you cannot drop any points," Wenger said. "You can only give one answer, which is to win the game. I like the fact that we're mentally ready for a fight."

Wenger was full of praise for Wilshere, who set up Olivier Giroud's goal 59 seconds after he himself had put Arsenal in front. "Jack has found his change of pace back and his penetration. His game is about that. He's not only a passer, he's a guy who's incisive with the ball. That's his strength and for that you need to be at the top of your game physically. You can see it when he's training well physically. He's coming back to his best."

Although Alex Oxlade-Chamberlain made his first appearance since the opening day of the season, the downside for Wenger were injuries to Nacho Monreal and Tomas Rosicky. "Rosicky has a bad nose. I don't know if it's broken or not but it looks bad," Wenger said. "Tomas told me it was an elbow, but he doesn't know if he [Gabriel Agbonlahor] did it on purpose. Monreal was an accident but we have to check his metatarsal in the morning. He got kicked on the top of the laces." The game was held up for eight minutes in the first half after the Villa defender Nathan Baker was knocked to the floor when Serge Gnabry's shot struck him flush in the face. Baker left the field on a stretcher wearing an oxygen mask but his condition improved and he was later reported to be suffering from mild concussion. "He's a little bit groggy at the minute but he's OK," said Paul Lambert, the Villa manager. "He can't remember a thing about what happened."