Thistle defeated Clyde 3-2 at the Energy Check Stadium at Firhill to move on to the 10-point mark in Group F, with second-placed Hamilton away to Airdrie on Saturday.
In last night's other Group F match, Airdrieonians and Queen's Park drew 2-2 at the Penny Cars Stadium, with the Diamonds winning a marathon penalty shoot-out 12-11.
Ross County secured top spot in Group B by extending their 100% record with a 2-0 win over Forfar Athletic in Dingwall while St Johnstone saw off Brechin City 4-0 at McDiarmid Park.
Hearts needed a late double from Craig Halkett to come from behind to beat Stenhousemuir 2-1 at Tynecastle and move to the top of Group A.
