Gloucestershire 301 for 8 (Bracey 118, Taylor 53*, Dent 50) trail Somerset 312 (Davies 87, Overton 54) by 11 runs
James Bracey's sixth first-class century led Gloucestershire to 301 for 8 in reply to Somerset's 312 on the second day of the LV=County Championship match at the Cooper Associates County Ground.
Combining solid technique, sound shot selection and a high degree of concentration, 23-year-old Bracey enhanced his England prospects by contributing 118 in an innings spanning 12 minutes short of six hours.
Chris Dent made 50 and Matt Taylor a career-best 53 not out, while Craig Overton (3 for 60) was the pick of the Somerset bowling attack.
Gloucestershire began the day on 13 without loss, with Dent and Kraigg Brathwaite in positive mood. They took the score to 41 before the West Indies captain was pinned lbw for 18 by a ball from Overton that nipped back off the seam.
Dent struck Lewis Gregory for three successive boundaries, moving to his third half-century in as many innings, off 70 balls. But, without addition, the Gloucestershire captain aimed to work a straight ball from Marchant de Lange towards the short leg-side boundary and edged catch to wicketkeeper Steve Davies.
It was de Lange's first wicket for Somerset. He produced some pacey short balls, but Bracey and Tom Lace took Gloucestershire to 97 for 2 at lunch.
The afternoon saw Somerset's seamers, aided by some tight spin bowling from Jack Leach, exert greater control.
Seeking to break loose, Lace reached to drive a wide ball from Overton and lifted a catch to Tom Banton at cover.
Bracey pulled a six over fine leg off Overton. But, with the score on 119, Graeme van Buuren edged de Lange to second slip where Gregory held a diving catch.
Nothing seemed to perturb Bracey, who looked increasingly assured as he reached a half-century off 115 balls. Ryan Higgins contributed 23 to a stand of 41 before edging Josh Davey to first slip.
George Hankins fell lbw on the back foot to de Lange. But Bracey remained rock-like and was unbeaten on 79 at tea, taken with Gloucestershire 189 for 6.
George Scott went on the attack at the start of the final session, launching a big straight six off Leach.
But after helping Bracey add 26, Scott edged Gregory to second slip where Overton pouched a comfortable catch.
Bracey reached a chanceless hundred by glancing Davey to the fine leg boundary. He had faced 208 deliveries and hit 14 fours and a six.
Somerset took the second new ball at 217 for 7, but were frustrated as Taylor weighed in with a hugely valuable maiden first class half-century, made off 92 balls, with seven fours and a six.
Bracey's vigil finally ended when he edged Gregory to second slip. Prior to that, his only problem had been a broken bat on 107.