Worcestershire picked up a further three wickets on another rain-shortened day in the Specsavers County Championship encounter with Sussex at the 1st Central County Ground.
Wayne Parnell, Ed Barnard and Charlie Morris all picked up one wicket apiece as Sussex, who began the day on 150-5 from 50.4 overs closed on 299-8 from 85 overs.
Parnell then bowled the first ball of his 17th over but then went down clutching his left arm and was helped from the field shortly before tea.
The South African had earlier struck when play got underway at 3pm as 18-year-old debutant Tom Clark (13) went for a cut shot and nicked through to Riki Wessels who took a fine low catch away to his left at first slip.
The score was then 193-6 and without addition Ben Brown (33) was deep in his crease looking to work to leg when he was lbw to Ed Barnard.
Sussex were rescued by David Wiese and George Garton who added 96 for the eighth wicket.
But just before a premature close, Wiese (47) played all around a fine delivery from Morris which swung back in and he lost his leg stump.
Garton reached his half century off 65 balls with eight fours before play was halted for the day eight overs early because of bad light.
Barnard ended with figures of 20-4-64-3, Morris 18-3-63-3, Parnell 16.1-8-39-1, Finch 20-1-77-1, D’Oliveira 7.5-0-37-0, Mitchell 3-1-7-0.