However, hours later the club announced the travelling squad for the match on Twitter, with his name included - claiming the medical team has given an "all clear" verdict.
The defending champions got to the scoresheet when Luis Suarez scored from Jordi Alba's cutback eleven minutes into the match.
"He could play at the start, come off the bench, not play at all ... everything is possible".
Dembele was introduced for the ineffective Rafinha early in the second period and, despite struggling to get into the game, made a telling impact with his late leveller.
"We've always said we can play against anyone, and that still holds true". More than anything because he is one more [player] and so we have more to choose from.
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Messi's absence opened up a gap to be filled further forward and many expected the chance to be given to the 21-year-old Ousmane Dembele. "He is generous with his effort and today he was very good".
"Against Inter in Milan we must follow the line we did against Real Madrid or Inter at home".
Barca were without a win in four league games and defensive errors looked set to play havoc with their title challenge.
Despite having that cushion at the top, though, Valverde says his side will still be going all out for the win - a result which would see them qualify for the knockout rounds.
A draw against Inter will guarantee qualification from Group B while victory would secure top spot, with two games still to spare.
'With Messi, Barca's degree of unpredictability increases but their attitude is the same without him. If they must, they know they can function without him.