Celtic manager Ronny Deila has confirmed that captain Scott Brown will undergo a scan after injuring his hamstring during Sunday's pre-season friendly with Rapid Vienna.
The midfielder pulled up in the first minute at the Gerhard Hanappi Stadion before being stretchered off the pitch.
Brown could now miss Celtic's Champions League qualifier against KR Reykjavik on July 15.
"Scott has an injury. We think it is a hamstring but we don't know yet how severe it is," Deila is quoted as saying by Sky Sports News.
"Hopefully it's not big and he will be back quickly. He will have a scan and we will see what happens."
Celtic ended up drawing the game 1-1 after Teemu Pukki's 70th-minute strike had cancelled out Virgil van Dijk's early own goal.
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