Franck Ribery is the latest Bayern Munich player to be ruled doubtful for his side's crucial Bundesliga match against Bayer Leverkusen tomorrow.

The French winger was unable to complete yesterday's training session because of a muscle injury.

He was examined by team doctor Hans-Wilhelm Mueller-Wohlfahrt but a prognosis was not yet known.

Bayern, fourth in the Bundesliga, meet Leverkusen aiming to finish at least third and qualify for next season's Champions League. Leverkusen are in second place, five points behind leaders Borussia Dortmund.

Starting tomorrow, 36-year-old Joerg Butt will return as goalkeeper for the final five Bundesliga games to replace the erratic Thomas Kraft, the Bayern interim coach, Andries Jonker, said.

"I have to ensure Bayern Munich qualify for the Champions League. I think there's a better chance with Butt at the moment," said Jonker, the 48-year-old Dutchman.

"It's also not easy for Butt, but easier than it would be for Thomas. I have confidence Joerg will do his job well."

Bayern had said Thursday that midfielder Bastian Schweinsteiger is "very doubtful" to play this weekend because of an ankle injury.

The Germany international was hurt in a challenge by teammate Arjen Robben, ruling him out of yesterday's and today's training sessions.

Bayern already has to do without the services of Dutch winger Robben, suspended for two games after insulting the referee after last week's 1-1 draw at Nuremberg, and defender Holger Badstuber, who has accumulated five yellow cards.

Anatoliy Tymoshchuk is likely to return to midfield after playing much of the season in defence, as Jonker opts for experience.

"It's important that we're calm and confident, and that we do what we want to do," he said.

Leverkusen's coach is Jupp Heynckes (photo), who will take over at Bayern next season for his third stint at the club.

"It would be a great pleasure if my team won," said Heynckes, who was in his first stint at Bayern when Leverkusen last won in Munich, on 21 October, 1989.

"We're in a privileged situation. We're the best team in the second half of the season. And we're on the ball."

Heynckes, however, is concentrating on his current club, and insists Bayern’s fate is none of his concern.

“Expectations are always high in Munich,” the 65-year-old told Kicker on Thursday. “The incentive to be able to play Champions League in the coming season is hugely important. But I have no influence on that. Here and now, all that counts for me is Bayer Leverkusen.”

Heynckes acknowledged: “The public’s interest will be huge, perhaps in me even more because I’m switching to Bayern.”

He predicted a 2-1 win for his current side. “And then I’ll jump for joy!”

Dortmund’s top scorer with 13 goals, Lucas Barrios, will miss the game against Freiburg because of a groin injury, but Robert Lewandowski will start in his place.

Meanwhile, league top scorer Papiss Demba Cisse will hope to add to his tally of 20 as he helps Freiburg’s push for the Europa League.

Today, Hannover hope to consolidate third place with a victory at Hamburg SV.

Yesterday

Mainz-Borussia M’gladbach 1-0

Today

Cologne-Stuttgart

Hamburg-Hannover 96

Hoffenheim-Eintracht Frankfurt

Kaiserslautern-FC Nurnberg

Wolfsburg-St Pauli

Werder Bremen-Schalke

Tomorrow

Bay. Munich-B. Leverkusen

Bor. Dortmund-SC Freiburg