Madrid, Sep 19 (IANS): Real Madrid coach Carlo Ancelotti confirmed on Tuesday that his side will be without right back Dani Carvajal for their Champions League debut at home to Union Berlin on Wednesday night.

"He has a muscle injury. He will rest tomorrow and we will carry out tests," confirmed the coach in his pre-game press conference, reports Xinhua.

The absence of the Spain international opens the door for Lucas Vazquez to return to the starting 11, although Nacho Fernandez could also have his options.

"The Champions League is always special for this club. We will play with that mentality, that of facing something that is special. We are at home and facing a well-organized, forceful, solid rival. We will have to put intensity into it," said Ancelotti of his side's European debut.

Carvajal's injury means he can also be considered a doubt for Sunday's Madrid derby away to Atletico Madrid in the Metropolitano Stadium.

Real Madrid travel across town after winning their first five games of the season, while Atletico's positive start to the campaign was derailed by a 3-0 defeat in Valencia at the weekend, that coach Diego Simeone said was the worst performance in the 12 years he has been at the club.