Arsenal manager Arsene Wenger has admitted he appreciated the significance of Robin van Persie's move to Manchester United long before the £24 million transfer was sealed last summer.
Van Persie has been hailed as the player who can decide the title this season after a sparkling start to his United career, yet Wenger is not surprised by his former captain's impact.
"I don't need anyone to tell me how good he is," stated Wenger when asked about Van Persie's impact at United. "We knew when we sold him to United that that would be the case. He is one of the best strikers in the world, so you know he will score goals for them. He scored 30 for us last year.
"At almost 30 he is at the peak of his game. Now he uses all his qualities in a calm and intelligent. He has a high level of confidence in his qualities. He is more patient than he was five or six years ago. He stays up front, and you won't see him for maybe 20 minutes. Before he used to come back into midfield, but he uses his killer instinct much better now.
"What is painful is to see Manchester United so far in front of us."
Meanwhile, Wenger has suggested that a win against champions Manchester City on Sunday could kick start his side's season, as he is targeting improved performances at their Emirates Stadium home in the second half of the season.
"Beating City would help to improve the confidence of the team, that is very important," he added.
"You can see that confidence is important for every team. We have had positive results away from home this season and at home we are now getting back to positive results."