Lowland League title hopefuls Kelty Hearts' reward for knocking out Annan Athletic on penalties at Galabank last night is a home tie with Solihull Moors of the Vanarama National League.
Hearts Colts also face a trip to the Emerald Isle after seeing off Cowdenbeath at Prestonfield last night, but face a stern test against Waterford, who finished fourth in last season's League of Ireland Premier Division.
Elsewhere in the draw, Connah's Quay Nomads - who knocked Kilmarnock out of the Europa League - face a trip to League Two side Cove Rangers, Stenhousemuir host Welsh outfit The New Saints and Airdrie welcome Waterford's league rivals Bohemians to the Penny Cars Stadium.
Ayr United make the trip to Wales to face Wrexham, while Formartine United host Northern Irish side Glenavon.
Elgin will travel to Championship Dundee after winning an astonishing second-round tie 5-4 at Brechin last night while there are three all-Championship affairs as Inverness Caledonian Thistle take on Morton, Dundee United host Arbroath and Alloa travel to East End Park to face Dunfermline.
Raith Rovers will play League One rivals Falkirk after the Bairns eliminated Celtic Colts while Partick Thistle travel to Montrose for the first competitive meeting between the two teams in nearly 30 years.
Clyde play Queen of the South and St Mirren Colts host Stirling Albion in the final two matches of the third round.
Ties will be played on the weekend of September 7/8.