Ghana attacker Samuel Afum has been sidelined for two weeks by a muscle tear.
The 23-year-old suffered the injury during warm-up of Young Boys' 2-0 win over St. Gallen in the Swiss Super League last weekend.
Young Boys boss Martin Reuda maintained the former Hearts of Oak playmaker in his starting line-up for the game and he lasted till the last 20 minutes of the game.
Club doctors assessed the extent of the damage on Tuesday morning and have asked the striker to spend two weeks in the treatment room before returning to the pitch.
Afum will the crucial trip to FC Basel on Sunday and is also likely to sit out of the home tie against Sion on March 17.
"I've been treating the leg and everything is going fine. Its bad missing those two games but I hope I return soon for the club," he told Ghanasoccernet.com.
Afum, who joined Young Boys from Egyptian Premier League side FC Smouha has featured in all three games for the club since FIFA issued a provisional ITC to clear him in mid February.