The Spanish midfielder, a key figure under Hansi Flick, has suffered a minor myofascial injury in the abductor muscle of his right leg, ruling him out for three weeks.
The 26-year-old had started six consecutive matches, including Thursday's La Liga clash against Osasuna, but he won't make it seven after limping off in the 28th minute at Montjuic.
The club confirmed the diagnosis on Friday afternoon, revealing the extent of the injury following medical tests. While the lay-off isn't lengthy, it comes at a pivotal moment in the season. "It's a blow, no doubt," Flick said after the Osasuna match. "Dani's been vital for us, and we'll feel his absence."
Olmo still managed to leave his mark against Osasuna, scoring before his early exit in the 1-0 victory. However, his injury couldn't have come at a worse time for Barcelona.
They face a crunch Copa del Rey semi-final second leg against Atletico Madrid on Wednesday, followed by a Champions League quarter-final showdown with Borussia Dortmund in two weeks. In La Liga, their lead is precarious, three points ahead of second-placed Real Madrid with plenty of football still to play.
Since joining from RB Leipzig, Olmo has battled to find his rhythm at Barcelona. His first season was plagued by registration issues and injuries, missing 10 matches across all competitions.
Despite that, he's featured in 28 games, carving out a role in the attacking midfield in recent weeks. Now, this latest setback stalls his momentum.
Flick has options to fill the void, with Gavi and Ferman Lopez likely to step up during Olmo's absence. The German boss will need to shuffle his pack carefully, especially after Olmo's recent stint with Spain during the international break.
The midfielder played in both of La Roja's Nations League quarter-final ties against the Netherlands, clocking 24 minutes in one and 84 in the other.
The road ahead looks bumpy, but Barcelona will hope their squad depth can keep them on track while Olmo recovers. For now, the Catalan giants must soldier on without one of their brightest sparks.
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