Somerset 463 (Hildreth 137, Trescothick 71, Gurney 6-106) beat Nottinghamshire 133 (C Overton 4-27) and 184 (Mullaney 54) by an innings and 146 runs
Craig Overton picked up a hat-trick as Somerset rounded off an impressive season with an innings victory over Nottinghamshire in their final Specsavers County Championship match at the season.
Overton's feat came just a day after his county team-mate and captain Tom Abell had picked up a hat-trick in Nottinghamshire's first innings.
The home side had begun the third day at Trent Bridge on 115 for 3 but within 10 minutes had been reduced to 119 for 6, thanks to Overton's three-in-three burst.
Notts rallied but were unable to survive the opening session, being bowled out before lunch for 184, leaving the west country side to celebrate victory by an innings and 146 runs.
Left-hander Ben Slater, who had passed 1000 first class runs for the season during the earlier part of his innings, nicked the ninth ball of the day to Marcus Trescothick at second slip for 49.
The next two deliveries were identical to each other, as right-handers Samit Patel and Riki Wessels both edged into the waiting hands of Trescothick - who became the first outfielder since GJ Thompson of Northants in 1914 to take three consecutive catches.
For Craig Overton it was a second first class hat-trick, after his exploits for MCC against champion county Middlesex in Abu Dhabi last year.
"Obviously it was my first over and I sent down a couple of looseners, then it came out alright and I got going with the first one," he said. "The one to the left-hander [Slater] swung a bit and nipped away. Then it was the right-handers [Patel and Wessels]. I always enjoy bowling to right-handers if it's swinging. The one to Riki bounced a little bit and caught the top of the bat on it's way to Tres. Then I was away on a long run to celebrate."
Notts, who knew they were already safe from the drop into Division Two, showed some fight as Ben Duckett and Tom Moores resisted for almost an hour before Duckett was given out lbw to Lewis Gregory, who then had Luke Wood caught behind for 4.
Josh Davey, who took 3 for 20, completed the formalities. He had Moores caught behind for a dogged 17 and then pinned Matt Carter lbw for 22, which included a huge pulled six off Craig Overton.
Somerset's victory also confirmed their status as Division One runners-up, and they will be playing Notts again next year, who narrowly survive over Lancashire, having picked up one more victory than the Red Rose.
"We didn't play well enough and there will be frustrated members out there. We're frustrated about it because we have had a tough six weeks to finish the season," Peter Moores, the Notts head coach, said. "Our goal was to stay in Division One and we've done that. I look back over the whole 18 months and we've won two trophies, got promotion and had a couple of cup quarter-finals, we've had highs and we've had tough days and today was a tough day.
"We've had a small staff and picked up injuries and come up short this week but all credit to Somerset and the way they played."