Barcelona forward Paco Alcacer suffered an injury blow on Sunday during his team's tussle with Deportivo La Coruna, picking up a muscular problem in his left leg.
Barcelona confirmed the issue via their official website.
Alcacer will miss the next three weeks, meaning he will be unavailable for El Clasico against Real Madrid at the Santiago Bernabeu on Saturday.
A club statement said when they expect him to return: "If all goes well then the player could be back for the game against Levante on 7 January, which is to be played three weeks from today. In the short term, Alcacer will miss the Clasico on 23 December in the Santiago Bernabeu and possibly the first leg of the Copa del Rey last-16 tie against Celta on 4 January."
The forward's first season at the club was a struggle; it took him until February to score his first La Liga goal, netting in the 3-0 win against Athletic Bilbao.
Alcacer is a supporting member of the Barcelona squad, although he has enough quality to become a vital figure to have around.
The 23-year-old is sharp around the penalty area, usually first to react to loose balls and able to latch on to passes from his team-mates. Should his confidence return, he can be an asset.
Barca manager Ernesto Valverde will hope so, as it takes some of the attacking burden off Messi and Suarez. With so many matches in quick succession, he will need to play his part.
So while Barcelona are in possession of attacking quality to match anyone in world football, Valverde will want to see Alcacer back in action quickly. He's capable of offering a different edge that can aid the Blaugrana in their quest to dominate on all fronts.