He took 31 wickets this season and should be a demanding pick in the auction next year.
Worcestershire emerged as the champions of the tournament.
He played the league stages for them this season.
Jamie Overton's 5-wicket haul does the job for Somerset.
It was yet another one-sided affair.
Evans was the star of the game.
He scored 37 runs off the same number of deliveries.
With a win here, Lancashire will now progress to the semifinals of the tournament.
As collateral damage, Stokes will be unavailable for Durham's T20 Blast quarter-final against Sussex.
Roy made the mistake of flinging his bat onto the ground out of frustration.