Worcestershire all-rounder Ed Barnard produced his second five wicket haul of the game to follow on from a half century on day two of the Specsavers County Championship match with Somerset at the Cooper Associates County Ground at Taunton.
The former England Under-19 player had experienced his maiden five-for in the first innings – 5-52 – and topped that with figures of 19-8-37-5.
Barnard had also earlier in the day struck a fine 50 as Worcestershire totalled 179 all out to trail by only 23 on first innings after recovering from 48-5.
But an unbeaten century from James Hildreth enabled the home side to reach 255-9 by the close of another see-saw day – an overall advantage of 278.
Morning rain prevented play getting underway until 1.10pm, when Worcestershire resumed on 153-8.
Josh Tongue was caught at cover off Lewis Gregory for 10 but Barnard had time to complete 50 off 64 balls with nine fours before he was bowled by Craig Overton.
Gregory was the pick of the Somerset bowlers with 4-51 from his 10 overs.
Somerset lost Eddie Byrom to the fifth ball of the innings to Joe Leach for a duck and the Worcestershire skipper then accounted for first innings century-maker Matt Renshaw for seven with the total on 11.
Marcus Trescothick and Hildreth added 64 between them before the opener was out for 43, edging Tongue through to keeper Ben Cox.
By the time that tea was taken Somerset had moved onto 107 for three with Hildreth unbeaten on 36 and Abell 16 not
Hildreth, who was dropped before he had scored at third slip and later at first slip, went to his half century with a boundary to fine leg, his runs coming off 85 balls with eight fours.
But then Barnard moved onto centre stage with the ball for the second time in the game.
Somerset skipper Tom Abell (27) was caught at first slip by George Rhodes off Barnard, his fifth wicket partnership with Hildreth adding 70 runs.
Steve Davies (5) became another victim of Barnard – lbw and in the same over the bowler struck again this time removing Gregory caught at cover, which made Somerset 153 for six.
Craig Overton hit some lusty blows to bring up the 200, before he was bowled by Steve Magoffin for 22.
Hildreth continued to score quite freely despite losing the services of Josh Davey and Jack Leach to Barnard, the latter of which provided him with his 10th wicket of the match
In the last over of the day Hildreth went to his 100 with a boundary off Tongue, his runs coming off 153 balls with 15 fours.