Matthew Upson knows he will have to be at his best to shackle former team-mate Nicklas Bendtner this afternoon.
The West Ham United defender and Arsenal striker shared a dressing room at Birmingham City during the first half of the 2006/07 season, before Upson moved to the Boleyn Ground in January 2007.
The pair played seven times together, with both getting on the scoresheet in a 3-0 win over Plymouth Argyle on 2 December 2006, and the England centre-back knows he will have to be alert to deal with the threat posed by the powerful Denmark forward.
"I know Nicklas relatively well," said the 30-year-old ahead of Saturday's match, which will be screened live on ESPN and ESPN HD from 4.45pm. ESPN is available on Sky channels 417 and 442, Virgin channels 529 and 530 and Top Up TV 34.
"He's progressed as a player over the last 18 months. I played with him at Birmingham for a short while when he went on loan there.
"You know what you are going to get from him. He's a big physical presence who can bring the ball down well, and he's also a threat in the air. He's also got good feet as well, but he probably needs that little bit of consistency and clinical finishing in front of goal, but he's still young and, given the opportunities, he's shown he can take them, so we'll have to be ready for him."
Upson also spent five-and-a-half years at Arsenal between May 1997 and January 2003, when he moved to Birmingham for £1m.
During his time at Highbury, the Suffolk-born player worked under Gunners manager Arsene Wenger, and quickly became a convert to the Frenchman's preferred style of play.
That said, Upson is treating Saturday's trip to the Emirates Stadium like any other Barclays Premier League fixture.
"I wouldn't say it is special [to go back to Arsenal]. It's always nice to go back there, but I've been left quite a few years now, so in my mind, it's just another away game for West Ham United.
"When they have got the wind in their sails, there are probably not many better teams to watch in the Premier League, and maybe even in Europe. They are highly entertaining and have a lovely style of play, and we will have to be really on our guard if we want to take something from the game.
"We've got a fairly good recent record there. We obviously got a massive win there the season we stayed up and we got a good point there last season with a really big team display, so it shows that it can be done and we're capable of doing it."