Connor McManus has joined Morton on a six month contract.
The midfielder was released by Celtic at the end of last season after coming through the ranks at the club.
In 2015 he captained the hoops to a 5-2 SFA Youth Cup win over Sevco at Hampden but never managed to make the transition to the first team.
In 2015/16 he was on loan at Alloa Athletic and spent the latter part of last season on loan at Queen of the South.
Morton boss Jim Duffy has taken a number of players from Celtic in recent seasons including Aidan Nesbitt, Jamie Lindsay, Luke Donnelly, Paul McMullan and Mikey Miller.
There was no dream debut for the midfielder with Motherwell beating Morton 4-0 yesterday in the League Cup at Fir Park.
On Saturday Morton complete the group stage at home to Edinburgh City realistically looking for a win to stand a chance of progressing as one of the best runners up.
