Partick Thistle 4-2 Ayr United
Partick saw off a spirited Ayr side in a thrilling encounter at Firhill Stadium.
The visitors got off to a flying start when Keigan Parker was on hand to fire home Adam Dodd's cross after four minutes.
Partick levelled things up 10 minutes after the restart when Kris Doolan unleashed a fine volley from the edge of the area.
Doolan claimed his second as the Jags took the lead nine minutes later, this time heading home Chris Erskine's cross.
Victory was all but ensured when Ross Robertson felled Paul Paton inside the area with 10 minutes to play - Paul Cairney stepped up to convert the kick.
Michael McGowan set up a tense finish when he pulled a goal back with a stunning long-range effort three minutes from time.
But Cairney settled any nerves immediately when he poked home Doolan's ball a minute later.
Partick: Fox, O'Donnell, Cole, Archibald, Sinclair, Cairney, Rowson, Paton, Erskine (Bannigan 90), Doolan, Elliot (Naismith 73). Subs Not Used: Scully, Stewart, Scott Robertson.
Goals: Doolan 55, 64, Cairney 81 pen, 90.
Ayr: Cuthbert, John Robertson (Ross Robertson 58), Malone, Smith, Dodd, McGowan, Geggan, Tomsett, Moffat (McKernon 81), Parker, Roberts (Wardlaw 69). Subs Not Used: McWilliams, Shankland.
Booked: Parker, Ross Robertson.
Goals: Parker 4, McGowan 88.
Referee: Calum Murray