Venue: Victoria ParkDate: Sunday, 12 October Kick-off: 1500 BST Coverage: Regular updates on BBC Radio Scotland 810MW
Andy Dowie sealed the win for County with six minutes to go.
Dyron Daal hit a double as Ross County strolled past Morton to reach the Challenge Cup final.
County striker Steven Craig knocked home the opener in the sixth minute when he pounced on a Martin Scott lay-off inside the box.
Daal's header made it two before the break and then doubled his tally in the 62nd minute with another header.
Peter Weatherson pulled one back with a late free-kick in the 77th minute before Andy Dowie sealed the win.
Ross County: Bullock, McCulloch, Keddie, Dowie, Boyd (Watt 76), Strachan, Hart (Gardyne 71), Brittain, Daal (Higgins 83), Craig, Scott. Subs Not Used: Soutar, Lawson.
Goals: Craig 6, Daal 42, 62, Dowie 84.
Morton: Cuthbert, Harding (Paartalu 63), Smith, Shimmin, McManus, Masterton (Weatherson 51), McGuffie, Jenkins, Wake (Finlayson 60), Russell, McAlister. Subs Not Used: Stewart, MacGregor.
Sent Off: McManus (55).
Booked: Cuthbert, Smith.
Goals: Weatherson 77.
Ref: M Tumilty