Arsene Wenger hailed two-goal Alexis Sanchez as he took his tally to seven in the Premier League since his arrival from Barcelona.
The Chilean netted the first and third goals in an electric display, and Wenger said: “It was a top performance from Alexis Sanchez.
“His quality is exceptional, he takes responsibility and goes at people. He fights, he can score, that is what you want from great players.”
Arsenal had to wait until the 71st minute for their first goal, and Wenger added: “It was a question of patience and quality and I think we did all of that.
“It was important not to concede a goal and in the end it was a comfortable win but everyone works hard in the Premier League.”