CARLTON young gun Patrick Cripps could be sidelined for up to a month after suffering a fractured fibula in the VFL on Saturday.

The 19-year-old midfielder copped the leg injury while playing for Carlton's VFL affiliate, the Northern Blues.

Cripps' injury is a disappointing blow for the rebuilding Blues.

Last year's No.13 draft pick has played two matches this season and was fighting to regain his place in the senior side.

His injury is similar to that suffered by tagger Ed Curnow in the drought-breaking round five win over the Western Bulldogs.

Meanwhile, an infected broken finger is behind hard-nut midfielder Tom Bell's absence from Monday night's clash against St Kilda at Etihad Stadium.

Bell had surgery after suffering the injury in round five and missed one match before returning in the humiliating loss to Collingwood last round.

"Certainly no damage as such, but the wound just got infected – the wound where they put the plate in," Carlton football operations manager Andrew McKay said. 

"It's just unfortunate and quite possibly could have been a reaction to the stitches. 

"He's had that fixed up and he's on antibiotics so will be back fit and healthy after the bye." 

Carlton could regain key players Chris Judd (hamstring), Andrew Carrazzo (back) and Jarrad Waite (back) after the round nine bye, according to the Blues' website.