Carlo Ancelotti opted to rest Hummels for the 4-1 Bundesliga win over Borussia Dortmund on Saturday with an eye on Wednesday's encounter at the Allianz Arena, but misfortune struck on Sunday when the centre-back suffered an ankle injury in training.
Matthaus sees no reason for concern, though, and feels Javi Martinez and Jerome Boateng are more than capable of holding their own in defence in Hummels' absence.
"It's a real shame for Mats and for Bayern. He has been in great form all season," Matthaus told AZ.
"A world-class defender is missing now that Mats is unavailable, but I believe in Boateng and Martinez. It has become a bit easier for Ancelotti to make a decision.
"Boateng is still missing a bit of match rhythm after his injury, but he rose to the occasion against Dortmund and will do the same versus Madrid.
"And Martinez has proven his worth at centre-back. He has really grown in this position."