The debutant tipped over a snapshot by Adam Barrett then had to save low down by his left-hand post when Legge struck a low effort.
Gillingham took the lead in the 44th minute when McDonald put the Carlisle rearguard under pressure and as the ball broke to Pigott the on loan Charlton striker drilled a low shot past Pickford from 15 yards.
Carlisle's Michael Drennan's luck was out with a powerful 35-yard effort on the stroke of half time which came back off the post with keeper Stuart Nelson beaten all ends up.
Again Carlisle were denied by the woodwork in the second half when Miller's downward header from James Berrett's corner struck the foot of the right-hand post.
Carlisle piled on the pressure in search of the equaliser, but left themselves short at the back allowing McDonald to profit in the 88th minute, finding space to slip the ball wide of Pickford.
There was just time for Carlisle to grab a goal when Legge headed past his own keeper after the ball had come in from the left, but Gills held on.
- Sports & Recreation
- Jordan Pickford
- Leon Legge