|Specsavers County Championship Division Two, Swansea, day three|
|Northants 321 and 230-7: Evans 73; Carey 4-77, van der Gugten 3-45|
|Glamorgan 236: Selman 122*; Azharullah 3-58, Sanderson 3-67|
|Glamorgan 4 pts, Northants 6 pts|
Northants go into the final day strongly placed with a lead of 315 over Glamorgan with three wickets in hand.
The visitors took a first innings advantage of 85 despite the heroics of Nick Selman, who batted through for 122 not out, his maiden century.
Northants raced to 230 for seven, Laurie Evans impressing again with 73, despite four wickets to debutant Lukas Carey.
The visitors could declare early on day four to allow time to force victory.
Selman became the first Glamorgan player to bat through a Championship innings since Matthew Elliott in 2004, while Ruaidhri Smith was the next highest scorer with 25.
Smith was left unable to bowl with a suspected rib problem, while Northants' Sean Terry batted down the order with a back problem.
But Rory Kleinveldt (32 off 17 balls) joined Evans to demonstrate his powerful hitting for the second time in the match.
Despite the wicket-taking feats of teenager Carey, who has seven victims in the match, Northants should have enough runs in the bank to declare on a ground not known for big last-day scoring.
Glamorgan batsman Nick Selman told BBC Wales Sport:
"I was lucky to get dropped first ball of the day, so it was good to get through that, and to get to three figures was great.
"I got to 100 pretty quickly thanks to a few edges- the quicker you can do it, the less nervous you get, so it was good to knock them off quickly.
"If we'd got 50 more, the game would have been really in the balance, but we're confident we can get three quick wickets and knock off whatever they post.
"Lukas has bowled very well in this game, playing with him in the twos, he's a strike bowler, he's shown it in this game and I think he'll have a pretty good career."
Northants all-rounder Rob Keogh told BBC Radio Northampton:
"It was a used pitch when we came here so it's going to start misbehaving, we've already seen it was going up and down from their seamers, and there's a lot of rough for the left-handers in their top order.
"I think we'll have another little go (batting) in the morning, try and hit a few quick runs.
"If we have another four or five overs we can get a score potentially out of their reach and get into them.
"The task for Loz (Laurie Evans) and me was to try to build a platform for Rory (Kleinveldt) and Whitey (Graeme White) to play their shots, because it seems to be about getting through the new ball on this wicket."