Charlie Mulgrew is a doubt for Celtic's William Hill Scottish Cup fourth-round tie against Hearts at Tynecastle on Sunday.

The Hoops midfielder injured his ribs in Thursday night's 3-1 Europa League Group D defeat by Salzburg at Parkhead.

Defender Jason Denayer missed the game with a foot injury and is also a doubt while Swedish striker John Guidetti, ineligible for the group stages of the Europa League, returns while defender Mikael Lustig remains sidelined with a hamstring injury.

Provisional squad: Gordon, Matthews, Izaguirre, Denayer, Ambrose, Mulgrew, Van Dijk, Kayal, Brown, Johansen, Bitton, Commons, Scepovic, Forrest, Guidetti, Wakaso, McGregor, Griffiths, Tonev, Stokes, Zaluska, O'Connell.