Chelsea midfielder John Swift returned to Stamford Bridge on Thursday after a proposed loan move to Ipswich Town fell through due to injury.
The highly-rated midfielder was training with the Suffolk-based club in hope of earning a loan move following a disappointing spell in Yorkshire with Rotherham United.
Swift made just two starts and two substitute appearances for Steve Evans' side before the loan deal was cancelled at the beginning of November.
Despite his failure to make an impact at Rotherham, the former Wolves manager was keen to have a close look at the England Under-20 international and with Chelsea's blessing, he spent a few days training with the Championship's fourth placed side.
After impressing, it was thought on Wednesday that a deal for Ipswich to bring the player in on loan was imminent. However, with just hours to go before the loan window closed, McCarthy revealed the youngster had picked up an injured and couldn't guarantee how long he would be out for.
''We would have taken him because we were really pleased with him,'' McCarthy was quoted as saying by EADT24.
''He just got a knock and we don't know how long he'll be out for. It's not worth the risk - for him and us. It might be one we look at again in the future.''
The injury is a huge blow for both Ipswich and Swift as the deal could have really helped both parties. Despite not being one of the more fancied sides in the division, Ipswich have shown their promotion credentials in the early part of the season and sit just four points off first-placed Derby County.
The under-21 Premier League winner, who is looking to put the bad loan spell at Rotherham behind him, would have undoubtedly boosted their quality in midfield heading into a busy December.
Mick McCarthy's men play three of the current top five within the next seven games, a period that could ultimately define their season.