An explosive spell from NSW young gun Chris Tremain has given the Blues a chance of snatching outright victory over Tasmania on day four of the Sheffield Shield match at Bellerive.

Tremain grabbed the Tigers last four wickets in eight balls as the home side were all out for 245 in their second innings, a lead of 170.

NSW will win a match that had looked destined for a draw if they can reach their target of 171 in 25 overs with a required run rate of 6.84.

Tremain took 4-0 as the Tigers lost their last four wickets for just four runs, the 21-year-old finding himself on a hat-trick in his 12th over.

When the home side came back from tea at 6-234 a draw looked almost certain.

But Tremain bowled first innings century maker Jason Krejza (11), then had Evan Gulbis caught behind with successive deliveries to have Tasmania 8-241.

He delivered a hat-trick ball to Ben Hilfenhaus he’d rather forget but had the Test paceman on his way for a duck two balls later when he knocked over the stumps again.

The Tigers were all out when Adam Maher was trapped in front by Tremain, their last three batsman all making ducks.

Dubbo product Tremain, playing just his third first class match, finished with his best figures of 5-57.

Earlier, the Blues had kept themselves in with some chance of an unlikely victory with a double strike in the space of three balls that removed Jonathan Wells (10) and Mark Cosgrove (92) soon after lunch.

The home side slumped from 3-174 to 5-174 with the dismissals and they were 6-226 when century-maker Nic Maddinson had Luke Butterworth (24) caught behind with his first ball of the Shield season.

Ricky Ponting was unable to repeat his first innings heroics, and was bowled by the last ball before lunch, a shooting off-cutter from Josh Hazlewood (2-54), for 12.