The Moroccan right-back picked up a right thigh injury during PSG's thrilling 5-4 first-leg win over Bayern Munich, and the club have confirmed he is expected to miss "the next few weeks" as he recovers.
That timeline effectively ends his involvement in the return match at the Allianz Arena on Wednesday, handing a significant setback to the French champions ahead of one of their biggest nights of the season.
Hakimi has been a key figure in PSG's European run, offering both defensive stability and attacking threat down the right flank. His absence removes one of their most dynamic outlets in a match where fine margins are expected to decide the tie.
With no direct replacement of Hakimi's profile in the squad, manager Luis Enrique is likely to turn to Warren Zaire-Emery to cover at right-back. The young midfielder started centrally in the first leg but is now expected to be asked to adapt to a deeper, wider defensive role in Munich.
PSG travel to Germany with a narrow advantage after a chaotic first meeting, but the loss of Hakimi adds a new layer of difficulty as they attempt to reach the Champions League final.
Bukayo Saka has said Arsenal would head into next week's Champions League semi-final second leg with confidence after securing a hard-fought draw away to Atlético Madrid in Spain.
Diego Simeone has insisted Atletico Madrid were the better side despite being held to a 1-1 draw by Arsenal in the first leg of their UEFA Champions League semi-final on Wednesday night.
Jobe Bellingham has said he planned to stay at Borussia Dortmund for the long term after reflecting on a positive first season in Germany.
Mikel Arteta was left angry after Arsenal were denied a late penalty in their 1-1 UEFA Champions League semi-final first-leg draw against Atletico Madrid on Wednesday night.
