Richard Oliver scored a rapid half century for Worcestershire who reached 112-4 from 29 overs on the opening morning of the LV = County Championship match with Gloucestershire at New Road.
Worcestershire were put into bat on a green-tinged pitch and Oliver was quickly into his side with a four backward of point off Craig Miles.
The left hander then cut, drove and pulled David Payne for three boundaries in quick succession.
But Worcestershire skipper Daryl Mitchell registered his first duck of the season with 17 on the board when he was adjudged lbw against Miles with a ball which kept low.
Oliver continued to score at a healthy rate although he had one slice of good fortune with an edge over the slips for four off Miles.
Tom Fell, who finished as Worcestershire's leading scorer in the Royal London One-Day Cup, edged through to wicket-keeper Gareth Roderick on seven to provide Miles with his second wicket.
The 50 came up in the 12th over and new batsman Alexei Kervezee on one was dropped at point off Miles.
Oliver was dealing almost exclusively in boundaries and reached his half century off just 46 balls with 12 fours out of 74-2.
It was his fourth score of 50 or more in his fourth Championship appearance for the county.
But after making 52 he nibbled at a Benny Howell delivery and was caught behind to leave Worcestershire on 81-3.
The 100 came up in the 23rd over but in the penultimate over before lunch Tom Kohler-Cadmore (7) provided Roderick with his third catch.
Kervezee remained unbeaten on 31 at the interval