Worcestershire 273 and 117 for 5 (Libby 55*, Dawson 2-36) need 277 runs to beat Hampshire 462 and 204 (Dawson 51, Virdi 4-108)
Liam Dawson returned 50 wickets in a Vitality County Championship season for the first time after scoring an eighth fifty of the season as Hampshire closed in on victory over Worcestershire.
Spinning all-rounder Dawson reached a half-century of scalps by adding Kashif Ali and Adam Hose to his tally - in doing so beating the 49 wickets he claimed last season - with no spinner in the country taking more this year.
Along with his bowling exploits, no one has passed 50 more times than Dawson in Division One in 2024, as he moved to 907 runs with a 51 which set Worcestershire 394 runs to win.
The visitors ended the day five wickets down, still 277 runs short of victory - but with Jake Libby still undefeated on 55.
Both sides are now only playing for positions after Hampshire's improbable title challenge ended with Surrey's victory over Durham, and Worcestershire's survival already secured.
Having elected against enforcing the follow-on the previous evening, Hampshire's second innings was ramshackle and lacking in fluency, but still ended up at in the vicinity of the destination they would have aimed.
The inability to score runs quickly was largely due to Joe Leach's expertise with a nipping ball, taking three for 17, with six pressure-building maidens, across his first two spells.
The 33-year-old is retiring after next week's fixture against Lancashire, but proved he was still as skilful as ever to pick up Hampshire's top three - although none of the wickets were classic dismissals.
Toby Albert fell in the second over of the morning when he was strangled down leg and was caught behind, Fletcha Middleton lasted a further four overs before he was caught and bowled while playing across one, and first innings double centurion Nick Gubbins was caught at slip after the ball had looped off the wicketkeeper's glove.
Ben Brown quickly followed when Amar Virdi straightened one to pin him, but James Vince was keeping the scoreboard progressing with an often sketchy, sometimes glorious 44.
Vince dragged Virdi onto his own stumps while sweeping but after lunch Tom Prest and Dawson returned with a lucidly attacking game plan to whip up a 72-run partnership at a whisker under a run-a-ball.
Dawson followed his first innings century and five-wicket haul with a 63-ball fifty but fell soon after when Logan van Beek destroyed his stumps.
Things turned frenetic again as James Fuller swished behind, Prest was leg before when stuck on the crease to Virdi, Kyle Abbott was bowled on the swing and Felix Organ was run out after a strike confusion with Mo Abbas - which prevented Virdi from a second career 10-wicket haul.
With an imposing, but not impossible target, Gareth Roderick failed to show the resolve of the first innings by getting bowled by Abbott in the sixth over.
Kashif Ali played for turn that didn't come from Dawson to fall lbw in the 14th over before two fine slip catches from Vince accounted for Rob Jones and Adam Hose - the latter was Dawson's 50th wicket of the season.
Jake Libby had staunchly battled to 49, but when initially trying to reach the milestone, he ran out his partner Brett D'Oliveira, before eventually getting to a 47th first-class fifty with a less risky ambled single off 106 balls.
Libby remained unbeaten at close, with Ethan Brookes hanging on alongside him.