Berlin: Schalke 04 have reached the Champions League quarter-finals by the skin of their teeth but after Barcelona's shameful weekend defeat they will feel anything is possible when they host the Catalans tomorrow.

The Arena AufSchalke is an intimidating place to play at the best of times, so how Barca will react in Gelsenkirchen after their performance against Real Betis on Saturday, when they led 2-0 but ended up losing 3-2, is anyone's guess.

Schalke, UEFA Cup winners in 1997 but appearing in the last eight of the European Cup for the first time, are third in the Bundesliga after three wins and a draw in their last four games.

Barcelona, twice European champions, are also in third place in their league, yet scarcely will they have had such self-doubt before a first leg against second-tier opposition like Schalke.

"It is difficult to explain what happened," said coach Frank Rijkaard after his team shipped three goals in 15 second-half minutes. "All I can do is apologise to our fans. As a coach I feel ashamed at this result."

Rijkaard's room for manoeuvre is limited given that Ronaldinho is unlikely to take part because of leg muscle pain, while Deco, Rafael Marquez and Lionel Messi are all out injured.

Rijkaard may be tempted to recall Silvinho on the left side of defence after yet another shoddy display at the back, while Argentine centre-back Gabriel Milito could return after missing out on the Betis defeat because of groin pain.

Good defence will be important for Barcelona, who beat Celtic in the last 16, because Schalke know their best chance of an upset will be to attack with everything they've got.

"We have to get forward faster, to open up more opportunities," striker Kevin Kuranyi told reporters. "We need to create more chances."

Coach Mirko Slomka experimented on Saturday by playing full-back Christian Pander in an unfamiliar position on the left of midfield, with the in-form Heiko Westermann behind him.

"They worked well together," said Slomka, who will have to decide whether to play the same risky formation on Tuesday.

Possible teams:

Schalke 04: 1-Manuel Neuer; 18-Rafinha, 5-Marcelo Bordon, 20-Mladen Krstajic, 2-Heiko Westermann; 14-Gerald Asamoah, 13-Jermaine Jones, 8-Fabian Ernst, 24-Christian Pander; 22-Kevin Kuranyi, 19-Halil Altintop.

Barcelona: 1-Victor Valdes; 11-Gianluca Zambrotta, 5-Carles Puyol, 3-Gabriel Milito, 16-Silvinho; 24-Yaya Toure, 6-Xavi, 8-Andres Iniesta; 27-Bojan Krkic, 9-Samuel Eto o, 14-Thierry Henry or 7-Eidur Gudjohnsen.

Source : UNI