Thiago Motta (Photo: Reuters)
"He has a problem with his groin. Perhaps he will be available for the return leg," Ancelotti told a news conference on Thursday ahead of the match at the Parc des Princes.
However, the Italian coach urged his team to focus on Friday's Ligue 1 game at home to French champions Montpellier rather than their glamour European tie with Barcelona.
"We're at an important moment of the season. We must first think about tomorrow's game," said Ancelotti.
PSG lead Ligue 1 by five points from Olympique Lyon and have 58 points from 29 games, while Montpellier are seventh on 45.
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