Samuel Umtiti suffered an injury in only the second day since Barcelona resumed training sessions at the Ciutat Esportiva.
The centre-back sustained a problem to his right calf, the LaLiga leader confirmed in a short statement.
Barca was back training on Friday after players and staff were given coronavirus tests to ensure it was safe for them to return.
On Saturday, players were separated across three pitches in order to undergo sessions while maintaining social distancing.
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LaLiga teams have been granted permission to use training facilities again as part of gradual steps towards the planned resumption of the competition in June.
Barca WAS two points clear of Real Madrid at the top of the table when the season was suspended indefinitely in March.