Sidwell says he's learned from playing with the Greece international.
"You can always learn from players like Giorgos," he told fulhamfc.com. "He's been around the block, he's the highest-capped player for Greece, he's played in big competitions and he's won big competitions.
"Playing with him has been great, as well as it obviously has been with the other players that we've got. We've got experience throughout the team and that's great to learn from.
"Giorgos is playing well. He's come in and some people probably raised an eyebrow because of his age but obviously his quality's showed and that's the most important thing. If you're doing well on the pitch then you're going to keep playing, and he's done that."