Gareth Rees again proved a thorn in Derbyshire's side when he rescued Glamorgan with a career-best 126 on day one of their Championship match.

The opener scored his third century against Derbyshire in two seasons to help his team post 257-8, before bad light and rain ended play at Derby.

Glamorgan had been in serious trouble when they slumped to 84-4.

Derbyshire were without their leading wicket-taker Charl Langeveldt but Jon Clare returned an impressive 4-16.

The home side's decision to put Glamorgan in would have looked even better if wicketkeeper Tom New had taken a straightforward chance off Clare when Rees was on 25.

Clare, who bowled seven maidens, was the pick of the Derbyshire seamers on a pitch which gave them plenty of assistance.

He broke an opening stand of 45 when he had Glamorgan captain David Hemp trapped leg-before for 16 with his first ball.

Derbyshire were left to regret New's fumble, Rees holding his team together as Tom Maynard fell lbw to Graham Wagg and Michael Powell had his off stump knocked back by Clare before he had scored.

When Jamie Dalrymple was brilliantly caught by Tom Lungley off the third ball after lunch, Glamorgan were four down, but Rees at last got some support from Mark Wallace who helped him add 63 in 17 overs.

Clare returned to have Wallace caught at mid on for 23 and then had Alex Wharf lbw to plunge Glamorgan back into trouble at 159-6.

But Robert Croft (37 not out) joined Rees in a stand which held up the home attack for 29 overs and made sure Glamorgan would reach a competitive total.

Rees hit two sixes and 13 fours in his 126 before being trapped lbw by off-spinner Wagg amid fading light.

Glamorgan lost Jason Gillespie to Wavell Hinds before the umpires took the players off shortly before an electrical storm hit the County Ground.