Glamorgan errors help Guptill
Martin Guptill took full advantage of Glamorgan's generosity to score his second century of the season for Derbyshire on Thursday.
Guptill's knock put the hosts in a strong position on the second day of the LV= County Championship match at Derby.
The New Zealand Test opener was dropped three times on his way to 132 and added 170 with skipper Wayne Madsen, who was unbeaten on 122 as the home side closed at 335 for five, a lead of 99.
Although former Derbyshire player Marcus North took three for 40 with his off-spin, Glamorgan's injury-depleted attack struggled on a good pitch and Guptill punished them by completing a hundred between lunch and tea.
Mike Reed claimed his first Championship victims but the bowlers failed to build up any sustained pressure which allowed the home side to take control after light rain delayed the start by 75 minutes.
With leading strike bowlers Graham Wagg and James Harris both missing, Glamorgan needed to take every opportunity that came their way but Guptill was given two lives before Derbyshire had reached three figures.
Skipper Mark Wallace failed to cling on to a difficult chance down the leg side off former England paceman Simon Jones when Guptill was 17 and the score 35, but Nick James' drop at mid-off when he was 65 was a bad one.
By then, Reed had celebrated his first Championship wicket by having Paul Borrington caught behind for 15 shortly before lunch but the afternoon session belonged to Guptill and Madsen who plundered 156 runs in 40 overs.
Guptill took three fours from a Reed over on his way to an 88-ball 50 and he moved into overdrive to reach his century, which contained 19 fours, from 143 balls.
Jones fluffed a simple chance at backward point when he was on 114 but after straight-driving James for six, he was lbw trying to whip Reed through midwicket three overs after tea.
But by then, Derbyshire were closing in on Glamorgan's 236 and Wes Durston contributed half of a 60 stand in 12 overs before he skied a sweep to deep square leg.
North took a return catch off a leading edge to remove Dan Redfern for a duck but Madsen patiently moved to his second hundred of the season from 192 balls to leave his side with a good chance of completing a Championship double over Glamorgan and a third victory of the campaign.