Coventry City have confirmed that Jordan Willis will miss up to six weeks while recovering from a knee injury.
The 19-year-old defender missed last weekend's win over Walsall after the problem flared up.
Manager Steven Pressley told the club's official website: "It's obviously disappointing for Jordan because he has come in for Cyrus [Christie] and acquitted himself extremely well, so we hope he makes a speedy recovery.
"Aaron Phillips has impressed though when he has made appearances, so while news of injuries is always disappointing, it's been encouraging to see our young boys stepping up to the mark."
Coventry currently sit 13th in the League One table.