Andres Iniesta could miss Barcelona’s Champions League second leg against Chelsea after suffering a hamstring injury.
Barcelona confirmed their key midfielder sustained the injury in his right leg during the first half of Sunday’s 1-0 LaLiga win over Atletico Madrid.
Iniesta tried to continue after feeling the problem around the 20-minute mark, but he was eventually replaced by Andre Gomes after 34 minutes.
Barcelona host Chelsea on March 14 in the second leg of their last-16 clash, having drawn the first game at Stamford Bridge last month.
Coach Ernesto Valverde told the club website: “Without Iniesta we lose a unique player, irreplaceable.
“It’s difficult to find a substitute for him because there is no-one like him in the world. Let’s hope the injury is nothing serious.”
Lionel Messi’s 600th career goal sank Atletico and ensured Barcelona stretched their lead at the top of the table to eight points.
The Argentinian struck with a trademark free-kick as Barcelona edged past their nearest rivals to take a huge stride towards regaining the title.
Atletico had clawed back the Barcelona’s lead to just five points but could not secure the victory which would have reduced the deficit to two.
Valverde added that the victory was “important for the title”.
However, he was adamant nobody at the Nou Camp would be celebrating yet with 11 matches still to play.
“We have made a step forward, but it is not definitive,” he said.
The teams drew 1-1 earlier in the season in Madrid but this time Atletico could not prise a point from the fixture.
Atletico boss Diego Simeone was proud of how his team fought, especially in the second half.
“It was a very even match, like the one in the first half of the season,” Simeone said, quoted on Atletico’s website.
“They had a good first half and in the second we reacted well and did what we could to try to score the equaliser.
“In the second half, we saw a hard-working team. We saw the team’s conviction.
“I always think about the next match, so we don’t stray from our objective, to keep improving.
“I think we’re close because we always compete in the best manner.”