Glamorgan 36 for 0 trail Northamptonshire 279 (Gay 65) by 243 runs
Having won the toss and elected to bat first, Northamptonshire reached 279 all out with runs for Luke Procter and Gus Miller helping them to recover from a middle-order collapse.
Three wickets apiece for Timm van der Gugten, Andy Gorvin and James Harris were the highlight for Glamorgan with the ball but with Northamptonshire having been 195 for 7 they will feel they let their opponents back into the game.
Glamorgan had seven overs to face before the close and they reached 36 without loss, 243 behind on first innings.
Northamptonshire won the toss and chose to bat but were pegged back early on by two wickets for James Harris. The first was Ricardo Vasconcelos who was bowled for 7. Harris claimed his second wicket in his next over when Prithvi Shaw edged a ball to Sam Northeast at first slip to leave them 19 for 2.
Gay continued his fine form with a patient and well-made 65 that included some lovely drives through the off side. He shared a stand of 90 with Proctor, the pair doing well against a Glamorgan seam attack that got the ball to move laterally throughout the day.
Gay was dismissed by one of those moving deliveries when he edged Gorvin to Marnus Labuschagne at second slip to leave Northamptonshire 109 for 3. A stand of 48 between Proctor and Rob Keogh took the visitors past 150 before both departed at the start of a spell that saw Northamptonshire lose four wickets for 28 runs.
Glamorgan’s bowlers were fantastic in the period before the tea break and made things very difficult for the batting side. There was a spell in the afternoon in which Lewis McManus faced 20 balls from Timm van der Gugten and he played and missed at eight of them, but it was Gorvin who trapped him lbw for 19.
Liam Patterson-White combined with debutant Miller for a stand of 37 that slowed the Glamorgan progress, but Patterson-White chipped a ball from Gorvin to Eddie Byrom at point for 30 with Northamptonshire still 18 runs short of claiming their first batting bonus point.
Miller and Raphael Weatherall managed to take Northamptonshire past 250 to claim their first point of the game as the old ball became a little easier to score against. Even after Glamorgan took the second new ball Miller continued to impress in his maiden first class match. His 40 included the only two sixes of the innings as he helped his team to what could prove to be a challenging total on this pitch.
Eddie Byrom and Billy Root successfully saw out the seven overs that were left to bowl at the end of the day without too many alarms as the inexperienced pair of Miller and Weatherall didn’t get the same movement that Glamorgan managed with the ball. They will be hoping that changes when the game resumes on Monday morning.