DOM Thompson and Chris Job scored centuries as Stroud shocked title favourites Dumbleton.
Earlier, captain Paul Frape won the toss and decided to bat on a good looking wicket. Luke Benneyworth and Adam Jones opened, but Benneyworth quickly fell for a duck.
Jones was playing some fantastic shots on his way to 29, but he miscued a pull shot to end an enterprising innings.
Job entered the fray with Thompson and they posted a 200-run partnership in 35 overs.
Thompson was first to reach his ton with Job only an over behind after smashing a huge six over mid- off. Stroud finished on 309.
In reply, Dumbleton raced to 85 without loss from just eight overs- Ross Martin hitting a quick-fire fifty. The tide turned when Job entered the attack to snaffle four wickets.
Captain Frape and James Job wrapped up the tail, and the evergreen Luke Palmer helped seal a magnificent Stroud victory by 180 runs.