It will be streamed live on the SPFL YouTube channel – WATCH HERE
The 14 second-round winners are joined in the hat by the 10 Ladbrokes Championship clubs plus Solihull Moors & Wrexham from the National League, Cymru Premier League sides The New Saints & Connah's Quay Nomads, Ballymena United & Glenavon from Northern Ireland, and Waterford & Bohemians from the Republic of Ireland.
The draw is unseeded but the eight ‘non-Scottish’ clubs will be kept apart.
Clubs and numbers
Pot A
1 The New Saints
2 Connah’s Quay Nomads
Pot B
3 Waterford
4 Bohemians
Pot C
5 Solihull Moors
6 Wrexham
Pot D
7 Ballymena United
8 Glenavon
Pot E
9 Dundee
10 Dundee United
11 Inverness Caledonian Thistle
12 Ayr United
13 Greenock Morton
14 Partick Thistle
15 Dunfermline Athletic
16 Alloa Athletic
17 Queen of the South
18 Falkirk
19 Arbroath
20 Raith Rovers
21 Montrose
22 Airdrieonians
23 Stenhousemuir
24 Clyde
25 Stirling Albion
26 Elgin City
27 Rangers Colts
28 Heart of Midlothian Colts
29 St Mirren Colts
30 Cove Rangers
31 Formartine United
32 Kelty Hearts