Glamorgan opener Gareth Rees top-scored as three of the Welsh county's batsmen reached 80 or more on a disappointing opening day for Gloucestershire.

Jim Allenby looked as though he was going to join Rees, Mark Cosgrove and Mike Powell in hitting more than 80 in the County Championship Division Two promotion clash, but he was dismissed in the penultimate over.

After winning a useful toss, Glamorgan reached 380-7 at stumps, hoping to register a fifth batting point early on day two.

With both sides still in the promotion hunt – Gloucestershire CCC in fourth and Glamorgan fifth – it is an important battle for points at Cardiff.

Glamorgan, looking to go one better than their near victory over Essex last week on the same ground, made a more than solid start with Cosgrove and Rees taking their side to 130-0 at lunch.

Though Glamorgan built scoreboard pressure, the opening pair struggled to get on top of some good new-ball bowling from Jon Lewis and James Franklin.

Glamorgan reached 50 in the 12th over as Cosgrove started to unleash some attacking shots as he raced to his half-century from 64 balls. Rees brought up the Glamorgan 100 in the 21st over.

The afternoon session started brightly enough, with Rees reaching 50 in the first over after lunch, but four overs later Cosgrove drove softly straight to mid-on off Lewis, having hit 80 from 93 balls. Gloucestershire continued their brief fightback when Richard Dawson trapped Will Bragg leg before to see Glamorgan go from 141-0 to 148-2.

There could have been a third wicket soon afterwards, with Powell surviving a leg-before shout and a near run out. He then nearly gave a catch to extra cover off Vikram Banerjee.

Gloucestershire CCC eventually struck when Rees holed out to cover off Franklin.

Jamie Dalrymple fell for a fourth-ball duck, going leg before to Banerjee, before Powell and Allenby took their side to 263-4 by tea.

But their stand – 112 in 32 overs – was ended when Powell, 16 away from his century, was bowled by Steve Kirby, before Mark Wallace top-edged to Steve Adshead off Lewis, who also claimed the important wicket of Allenby lbw.