Barcelona have confirmed that Thomas Vermaelen suffered a hamstring injury during the club's 5-0 victory at Real Betis.
Vermaelen, 32, limped off in the 41st minute at the Benito Villamarin to be replaced by Samuel Umtiti, who himself was returning from a hamstring injury.
A statement released by Barcelona said the Belgian centre-back would undergo tests on 22 January to assess the extent of the problem.
Lionel Messi and Luis Suarez both netted twice after Ivan Rakitic's 59th-minute opener to help Barcelona extend their unbeaten record in La Liga this season.
Barca head coach Ernesto Valverde was thrilled with Messi's performance after the Argentina international took his league tally for the season to 19 goals.
"You have to enjoy Messi. We're living at the same time as him we just have to enjoy him," Valverde was quoted as saying by Sport.
"I've played against him in the past and I know what he's capable of. Now I can enjoy him. It's spectacular to see him every day. He is the best player there is and the best there will ever be."
The Barcelona boss added: "It was a tough one tonight. Betis took risks and pressed high. It was tough because they went man-for-man all over the pitch.
"We struggled in the early stages because they changed their way of playing, with three at the back. As the game progressed, we got better. We persevered, they took risks and we punished them. Patience has given us the result."
Barcelona club-record signing Philippe Coutinho did not feature against Betis due to a minor thigh problem, although Valverde indicated last week that the Brazilian playmaker could make his debut against Espanyol in the second leg of the Copa del Rey quarter-final later this week.
"I'm reluctant to put an exact date on a start for Coutinho, but the progress of the injury is very positive," Valverde was quoted as saying by Sky Sports.
"He had a small muscular problem in his quadriceps, which is a particularly sensitive zone when striking the ball with power, but I hope he's soon with us."