Northants 59 for 2 trail Glamorgan 207 (Salter 59, Meschede 49, Gleeson 5-60) by 148 runs
Glamorgan, playing their first Championship match in Cardiff since June, bounced back from a poor start to make 207 before claiming two wickets in reply against a Northants side still holding promotion ambitions after their defeat of Sussex took them third-equal in the Division Two table
A partnership of 97 between Andrew Salter (59) and Craig Meschede (49) enabled Glamorgan to recover from 102 for 6.
It looked to be a good toss for Northamptonshire to lose early doors and it took just 1.5 overs for Richard Gleeson to strike, bowling Jacques Rudolph without scoring as he shouldered arms.
That left the young pairing of Nick Selman and Jack Murphy to begin the Glamorgan recovery against the opening pace attack of Gleeson and Rory Kleinveldt. Selman had looked to be doing just that before the young Australian-born opener edged to skipper Alex Wakely at slip off Muhammad Azharullah for 22. It wasn't long before Murphy followed him back to the pavilion, as he was trapped lbw by the same bowler for 12 with the home side soon in trouble again at 36 for 3.
Colin Ingram and Welsh youngster Kiran Carlson had added 39 before a light rain shower brought about an early lunch. However, Ingram lasted just one ball after the interval, clumsily caught by keeper David Murphy off Rory Kleinveldt off second slip. Carlson went in the next over, lbw to Gleeson for 10.
Chris Cooke was removed by Gleeson, caught behind and Glamorgan were 102 for 6 as the rain delayed play for the second time. The wicket brought Salter and Meschede together and, having waited 20 minutes to get off the mark, Meschede was almost caught at second slip before the ball trickled to the boundary.
After the scare, the batsmen piled on the pressure, although Northants had other chances. Salter had to kick the ball away from the stumps off Kleinveldt before Richard Levi dropped Meschede off Kerrigan at second slip.
Salter brought up his half-century from 100 balls before left-arm spinner Simon Kerrigan claimed two wickets in an over. Meschede fell one run short of his fifty when he was stumped to end a 97 partnership, before Marchant de Lange was bowled. Lukas Carey was bowled by Gleeson without scoring before he picked up his fifth wicket when Salter was caught at mid-on by Kleinveldt and Glamorgan were all out for 207.
Northamptonshire, in reply, started strongly racing to 24 in just 4.2 overs before Ben Duckett was caught by Jack Murphy at mid-wicket off Carey for 11. They had reached 49 when a Murphy off-drive found Carlson off Michael Hogan's bowling for nine.
Rob Newton (31 not out) and Richard Levi had added 10 runs when the players were taken off for bad light. Subsequently rain set in and Northamptonshire ended the day on 59 for 2.