JOHAN CRUYFF today lit the blue Dutch paper on tonight's Champions League Group H clash between Ajax and Barcelona.

Cruyff, a former player and manager of Barcelona, blasted the Catalans' president Sandro Roselli.

And he vowed never again to set foot inside the Nou Camp, the venue for tonight's powderkeg opening tie. Cruyff said: "I will support Ajax. I have had some differences with Barca's president, and I will not set foot in the Camp Nou as long as he is there."

And he warned his old club that new Brazilian signing Neymar could cancel out the contribution of Barca superstar Lionel Messi.

He declared: "They are too similar. Both want to dribble past players and both want too much of the ball."

But new Barca coach Gerardo Martino dismissed Cruyff's blast and said his only focus was on winning the Champions League.

The Argentinian said: "We're in three competitions and we have to reach the final stages of all three. When I took on the Barcelona job, I knew that if we didn't win a title this season it would be a failure.

"If I am here it's because I believe we can repeat the glorious moments of the club in recent seasons."

Barca go into the match looking to restore some defensive steel after shipping two goals in each of their last two league matches, even though both times they held on for 3-2 victories.

Martino said: "We have spoken about what has happened in the last two league games. Players have to make the right decision at the right time, be more direct when they can and be less direct when they can't. We have to correct things."