Arsenal boss Arsene Wenger says Denilson's form tonight will be key against Barcelona.

Wenger is counting on the Brazilian to keep the likes of Xavi in-check.

"We know that when you don't have the ball you need everyone on board, especially against Barcelona and on a pitch like the Nou Camp," said Wenger.

"We have to make the pitch smaller and everybody must work hard to win the ball back. That's where we failed in the first game, especially in the first half, and, of course, the heart of the battle will be won in midfield where Denilson plays.

"That's where Barcelona have the players who can dominate the game, especially Xavi, and a big part of the game will be decided there."