Morris finished up with figures of 5-24 and Leach 3-76, with Worcestershire trailing their opponents by 215 at stumps, after posting 35-2 from 18 overs in reply. ??
Marcus Trescothick (10) was the first of Morris??? victims, edging the 22-year-old to Ben Cox behind the stumps in the fourth over of the day.????
Morris and Cox combined again to get rid of Johann Myburgh and Tom Cooper, leaving Somerset 59-3 after 18 overs. And when Jim Allenby was caught by skipper Daryl Mitchell two overs later, Morris had claimed his fourth wicket of the day.
Alex Barrow (26), Lewis Gregory (30) and Jamie Overton (41) offered some resistance, but the visitors could only post a modest total of 250, with last man Alfonso Thomas remaining unbeaten on 12.
Mitchell finished the day unbeaten on 20 with Alex Gidman on seven, after Gregory had Richard Oliver caught and bowled before Thomas claimed the scalp of Tom Fell who was caught by Peter Trego late in the day.
In the weekend???s other match, Durham ended day two against Middlesex at Lords 157-4 in reply to the hosts??? first inning score of 463.
Keaton Jennings finished the day unbeaten on 61, with opener Michael Richardson and Scott Borthwick chipping in with 26 apiece before falling to James Harris and James Harris respectively.
Middlesex added 134 to their overnight score after being played into a great position by Sam Robson???s knock of 178, which spanned six hours on Saturday.
Neil Dexter forged a 58-run partnership with John Simpson for the seventh wicket with the latter hitting 10 boundaries in an eye-catching knock of 58 before he was caught by Rushworth off the bowling of Hastings (4-87).