Barcelona manager Ernesto Valverde said Lionel Messi will have a late fitness test ahead of Sunday's trip to Athletic Bilbao.
Messi has been recovering from a thigh injury suffered at Valencia last weekend, and he was restricted to around 30 minutes as a substitute in Barca's 1-1 draw with Real Madrid on Wednesday.
Per Marca's Ramiro Aldunate, when asked about Messi's availability for Sunday, Valverde said:
"As always, we'll have to wait to see how training goes before we decide, but the other day we didn't want to risk things.
"We're in a similar situation again and we'll decide based on how he is doing. At the moment he's okay, but we'll see what he says.
"It remains to be seen if he is going to be at 100 per cent or not."
According to Sport, Messi did recovery work in the gym on Friday rather than train alongside his team-mates.
The Argentinian resumed training as normal on Saturday, though, per ESPN's Samuel Marsden:
Barca will be hoping to have their talisman available for the trip. He's plundered an incredible 29 goals and 14 assists in 28 matches in all competitions this season.
The 31-year-old is particularly effective when present from the start, per Squawka Football:
Valverde will especially be hopeful he's fit to play, as he's anticipating a tough game at Athletic:
"Any match at San Mames is difficult and this one will be even more so because we know how tough Athletic will make it.
"Every game that Barcelona have played there has meant dealing with a great atmosphere and they will make it difficult for us to play.
"It will be a beautiful game to watch, but it will be one of the most difficult that we have left this season."
Barca resume their UEFA Champions League campaign on February 19 before taking on Real Madrid again on February 27 and March 3 in the Copa del Rey and La Liga, respectively.
Risking Messi before he's back to fitness and potentially losing him for those crucial clashes would be disastrous, but a win on Sunday is much-needed.
Real's 3-1 win over Atletico Madrid on Saturday cut Barca's lead in La Liga to five points. If they fail to beat Athletic, it could give their rivals a route back into the title race.