Lionel Messi gave fans reason for concern as he walked off the pitch during Wednesday's match against Atletico Madrid with what Barcelona initially diagnosed as a "knock."
Arda Turan replaced the Argentine in the 59th minute.
Several outlets suggest Messi may have aggravated a preexisting groin injury from earlier in the season. He was visibly upset on the bench as he assessed the problem.
TV replays show Messi coming out of a challenge by Diego Godin looking worse for wear.
Barcelona conceded an equaliser a minute later to Angel Correa in what was a tough couple of minutes for the host.