Former West Germany captain and coach Beckenbauer, commenting on the match for German television, criticised 36-year-old Buffon last week over Bayern's first goal in the last week's Champions League quarter-final first leg.
Beckenbauer said that Buffon moved like a pensioner after he was caught cold by a long-range shot by David Alaba which took a slight deflection and bounced in front of him as it flew into the net after just 25 seconds.
Bayern, who clinched the Bundesliga title on Saturday with six matches to play, went on to win 2-0.
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"Look at his positioning, he seemed like a pensioner," said Beckenbauer in an off-the-cuff remark during the halftime interval, adding that Alaba shot "from 120 metres away."
"He should have kept that shot out," added Beckenbauer. "Perhaps Gigi didn't think that Alaba would shoot from so far."
The comments brought an angry reaction in Italy, and especially at Juventus, where 2006 World Cup winning goalkeeper Buffon is regarded as almost untouchable.
Beckenbauer later apologised and Bayern coach Jupp Heynckes, possibly trying to build bridges before his side visit the Juventus stadium for Wednesday's return, heaped lavish praise on Buffon on Tuesday.
"Buffon is one of the greatest and best goalkeepers in football history," said Heynckes, remembering that Buffon stayed with Juventus when they were demoted following a match-fixing scandal in 2006.
"When Juventus were in Serie B, he showed himself to be faithful to the team, it was a great gesture," added Heynckes.
Bayern goalkeeper Manuel Neuer also trod carefully when talking about his opposite number.
"He's a great goalkeeper and the Juventus defence in general is very difficult to get past," said Neuer. "Maybe that shot took a deflection and we have to remember that he stopped us from winning 3-0."
Bayern's players showed a certain amount of disquiet after Juventus forward Mirko Vucinic was quoted as using the word war to describe Wednesday's match.
"Obviously, they want to give everything but it's maybe not the right word for a football match," said Neuer.
Winger Arjen Robben added: "War doesn't belong on a football pitch, we will simply give everything and we must be prepared. We have enough experience to deal with this kind of situation."
"That sort of vocabulary should not be used in football," added Heynckes. "Obviously, they want to correct what happened in the first leg, but that's not the right way of expressing it."
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