Azhar Ali hit his highest County Championship score of the season to help Somerset build a strong position going into the final day of the match with Hampshire at Taunton.
The experienced Pakistan batsman contributed 79 to celebrate his newly-awarded county cap as the division one leaders posted 358 for eight declared in their second innings – giving them a lead of 417.
Given an awkward four overs to bat in their second innings at the end of the day, Hampshire sent in Kyle Abbott to open with Ollie Soames in the absence of Joe Weatherley, who turned an ankle while fielding.
They closed on 12 for one, Soames bagging a pair of ducks when bowled by Lewis Gregory with the sixth ball, which jagged into him off the seam.
Tom Abell (58) and Tom Banton (70) joined Azhar in punishing some indifferent Hampshire bowling after the visitors had been bowled out for 349 at the start of the morning session to concede a first innings deficit of 59.
And it was a good day for all-rounder Gregory, who claimed the last two wickets, including his 250th first-class victim, before making a breezy 28 and sending back Soames.
Play began with the visitors 329 for eight in reply to 408. They added 20, Gregory removing the injured Tom Alsop, who again batted with a runner before lofting a catch to cover and Crane, caught at first slip chasing a wide delivery with just one run needed for a fourth batting point.
Alsop’s wicket brought up the 250 landmark for Gregory. Jamie Overton was unable to add to his second day victims and finished with five for 70 from 23 overs.
Somerset’s success this season has come despite a shortage of runs from their top order. Their biggest opening partnership in the Championship had been just 30, but Azhar and Abell put that right with an attractive stand of 128 in 29 overs.
Azhar, who went into the game averaging only 14, survived a close lbw shout from Abbott on 11 before gradually finding his form and moving to a fluent half-century off 63 balls, with 8 fours.
By lunch he and Abell had taken the score to 110 without loss off 23 overs and the afternoon session soon saw the Somerset captain complete his second fifty of the match, from 80 deliveries, also with eight boundaries.
Keith Barker was the pick of the Hampshire attack and forced a ball through Abell’s defences to bowl him, quickly following up by having first innings centurion James Hildreth caught at slip for two.
It was 165 for three when Azhar was caught at third-man attempting an uppercut off Abbott. But Banton confirmed his immense promise with a 73-ball half-century, including some sumptuous leg side boundaries and at tea Somerset were 236 for three, with a lead of 295.
The final session saw George Bartlett (33), Banton, Gregory, Dom Bess and Overton perish in the quest for quick runs and a declaration. Steve Davies was unbeaten on 36 when Abell closed the innings.
Hampshire leg-spinner Mason Crane again struggled for line and length in taking three for 122 from 24 overs, figures that meant he had conceded 210 runs from 36 overs in the game on a used pitch.