Manuel Almunia is confident Cesc Fabregas will help Arsenal win some silverware this season but is worried the midfielder could become 'bored' like Kolo Toure.
Ivory Coast international Toure sealed a switch to Manchester City earlier this summer to end a seven-year stint with the Gunners.
Almunia admits he was saddened by Toure's departure, although he can understand why the defender might have wanted a change.
"I was surprised by Kolo. He was a big part of Arsenal, one of the greatest players we've had over the last few years," said the goalkeeper.
"He was happy here and when I see him in the papers wearing a City shirt, it is very strange.
"But now we must work with different people. We have a new central defender in Thomas Vermaelen and must cope with this. In football people come and go. It's life.
"Kolo lived through great times at Arsenal. He won the league as part of a great team, the 'Invincibles'.
"But when you are at any place for a long time, you sometimes need a change and to change your way of life, the city where you live, the team-mates you see every day.
"Maybe he was a bit bored, a bit tired of being with the same people every day, in the same atmosphere.
"He needed a change and you could see it in his face he was not really, really happy in his last period at Arsenal."
More to offer
Almunia fears that Fabregas may also go in search of a new challenge at some point in the future, with the Spaniard again linked with a move away from Emirates Stadium in recent months.
Almunia nevertheless thinks that Fabregas has unfinished business with Arsenal and will enjoy a fine 2009/10 campaign.
"With Cesc, the same could happen but he has a lot more to offer Arsenal yet. Kolo gave everything to this club and won titles. He gave 100 per cent," said Almunia.
"With Cesc, this season we'll see the best of him and he'll help us win something. Then he'll be happy to be here and will do what he wants to do."