Derbyshire 43 for 0 trail Worcestershire 279 by 236 runs
Bangladesh captain Shakib Al Hasan moved into overdrive on his Worcestershire debut after opener David Wheeldon got stuck in the slow lane at Derby. Shakib raced to 90 off 82 balls while Wheeldon batted for just over three hours for 20 on his first Championship appearance of the season.
Tim Groenewald took three wickets to reduce Worcestershire to 66 for 4 but Shakib and James Cameron, with a career-best 89, carried the visitors to 279 with Derbyshire closing 236 runs behind on 43 without loss.
There had been plenty of movement for the seamers after Vikram Solanki elected to bat on a pitch which had been uncovered during the rain affected 40-over match against Gloucestershire the previous night. With the ball also swinging in the humid air, the batsmen had to struggle for survival and Wheeldon was beaten numerous times although Daryl Mitchell was the first to go when he got an inside edge into his stumps in the ninth over.
Solanki hit five fours before he mistimed a pull at Steffan Jones and Groenewald claimed his second victim when Moeen Ali was caught behind down the leg side in the penultimate over before lunch.
Wheeldon had scored 12 runs from 82 balls in the morning and he continued to play and miss repeatedly after the interval but Alexei Kervezee was next to go when he was lbw to a Groenewald inswinger.
Shakib attacked from the start and quickly passed Wheeldon whose laborious vigil ended when he top-edged a hook at Garry Park after facing 127 balls in 45 overs. Worcestershire then slammed on the accelerator as Cameron ,who was playing in only his third first-class match, and Shakib plundered 101 in just 16 overs.
Shakib reached 50 off 49 balls and then launched a punishing assault on Robin Peterson, hitting the South African left-arm spinner for 22 from seven balls while Cameron brought up the century stand by driving Greg Smith's off spin over the long-on boundary.
But in the same over, Smith ended Shakib's entertaining innings which contained 16 fours when he got one to spin to have him caught behind three overs before tea.
Cameron reached his half-century from 67 balls and although Peterson trapped Ben Cox lbw for 17, he came in for some more harsh treatment after Richard Jones had been smartly caught at slip off Smith who ended with impressive figures of 2 for 33 from 18 overs.
Cameron passed his previous highest score of 75 by driving Peterson for six and the Zimbabwean then hit the next two balls over long-off but his chances of a century were hit when Matt Mason was run out off a misfield.
Peterson had the last word when Cameron was caught at long-on going for his fifth six which left Derbyshire with 11 overs to negotiate. Although Chris Rogers survived a strong lbw appeal against Mason, he and Wayne Madsen played out the day with few alarms.