Gilberto Silva's smiling. No surprise: his apartment in Voula, a suburb on the south coast of Athens, looks out across the Aegean under a clear blue sky. It's 20 degrees in February and he's playing Champions League football in front of some of the most passionate supporters in Europe.

Evidently, there's life after Arsenal. The smile, though, is about something else. Tonight, Gilberto will lead Brazil out at Emirates Stadium for a friendly against world champions Italy.

He said: "It'll be great coming back; my first time in England since I left for Panathinaikos. But it will be emotional, too. I spent six years at Arsenal, maybe the best years of my career. I won't have much time but I hope I'll see everyone again, friends at the club and friends I made while I was living in London."

Gilberto, 32, joined Arsenal in 2002, already a World Cup winner. While at Highbury, he was part of some local history, too, playing a key role in 2003-04 when Arsenal were crowned champions without losing a game. Understandably, he's proud to have been an Invincible:

"That season is still very fresh in my mind," he said. "You know, we were always so sure we were going to win. The quality was there; confidence was so high. Everyone was focused on what we were trying to do together. A special time for us and for Arsenal fans, too."

During last season, though, Gilberto started only a handful of Premier League games as Mathieu Flamini emerged as Arsene Wenger's chosen partner for Cesc Fabregas in midfield. Weeks on the fringes turned into months, an experience which left the Brazilian frustrated.

"I never fell out with Arsene, whatever people say. I had to respect his decision even if I disagreed with it.

"We had good conversations but, when it came to talking about whether he still saw me as part of the team, it wasn't the conversation I expected. Maybe, I thought, it was time to leave Arsenal. I understood what the manager's idea was; he had so many good young players and, if I was in the team, they wouldn't have the chance to develop."

Last summer, Gilberto declined offers from other English clubs, not wanting to 'spoil the good story' of his time at Arsenal, and Panathinaikos made their move. He said: "Greece maybe wasn't an obvious choice but I wanted to refresh my mind and I'm enjoying it.

"It's good to experience a different mentality, a different culture. The club has great history and we're doing well in the Champions League.

"Even though we felt so at home in England, my family is settled and like it here."

Ironically, Flamini also departed the Emirates last July, leaving another, much younger Brazilian to shoulder extra responsibility in midfield during Arsenal's fitful season so far. Denilson has risen to the occasion recently - which comes as no surprise to Gilberto, who mentored the fresh-faced teenager when he arrived from Sao Paulo in 2006.

"He's a young player who really wants to reach the top. In time, I think he will. It's difficult for him and for the team at the moment, though, because they haven't been consistent. But Denilson is an intelligent player."

It's a challenge Gilberto sees in front of all the young players he left behind at the Emirates six months ago. The Gunners' last trophy-winning team, who lifted the FA Cup in 2005, have already been all but broken up. Has too much happened too soon in N5? Maybe, according to Gilberto.

He added: "It's only my opinion, and I could be proved wrong, but I think Arsenal made a mistake letting some of the more experienced players go. It would be good for the development of the younger players. They're having to learn for themselves and that's hard."

For all his misgivings about the short-term, however, Gilberto is convinced his old club's future is in good hands. He's full of admiration for Wenger's ability to develop young talent and impressed by his former manager's skills as an organiser.

"We all change our ideas from one year to the next. Arsene, too," he said. "He's like how all of us should be; he's open, wanting to try new things and to learn. Arsene is 100 per cent Arsenal."

And Wenger's current Arsenal team? Well, they're growing too, says Gilberto. Perhaps they've one very big lesson still to learn, though: how to win.

"What made that team in 2004 invincible is we had instinctive killers up front. The style now is similar, good passing, good technique. But even when we were under pressure we could give the ball to Thierry [Henry] or [Robert] Pires or [Dennis] Bergkamp or [Freddie] Ljungberg and the game would suddenly be over.

"These players need to find that killer instinct. They can get there but it takes time. I hope it comes quickly."

So, tonight's a kind of homecoming for a man who still loves the club he left last summer. He captains Brazil as the serial World Cup favourites continue to prepare for 2010 - and he wants to be in South Africa, of course.

But he's glad to be at the Emirates and added: "It's like Brazil's home in Europe. Everyone enjoys playing in front of a big crowd. But I think I'm going to enjoy it more than anyone else."