By Richard Clarke 

It was a week of contrast for Robin van Persie. The 23-year-old was left holding his head after missing a glorious early chance against Porto on Tuesday. Four days later Charlton keeper Scott Carson was shaking his as the Dutchman thumped a ferocious volley past him to win the Premiership game at The Valley.

It was Van Persie's 23rd goal in 88 appearances (45 as a starter, 43 as a sub) since moving from Feyenoord in 2004. His manager believes the Rotterdam-born striker is much stronger physically these days and is working hard on the mental aspects of his game.

"I felt when he came he had to adapt physically," said Wenger. "Today he is much stronger. You would be surprised how he resists challenges that he didn't two years ago. He looked a little bit lean and weak. We had to strengthen him.

"As well I think he is much more confident now. He reacts quickly so you need to focus more on the game. For example, the chance he missed against Porto, I think that was on his mind afterwards and he had not the same game. That is what he has to work on - not to let it pull you down, think about the future or the present. I think it's part of highly competitive people to be in the present, not in the past."

12/1 - Arsenal to win the 2006/07 Champions League

Copyright 2014 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source Richard Clarke 2 Oct 2006