Somerset 317 (Banton 132, Vaughan 44, Shakib 4-97) and 224 (Overton 49*, Banton 46, Shakib 5-96) beat Surrey 321 (Curran 86, Patel 70, Vaughan 6-102) and 109 (Leach 5-37, Vaughan 5-38) by 111 runs

Chasing 221 to win on a turning pitch, Surrey were bowled out for 111 with less than five minutes left in the game, 18-year-old Vaughan claiming five for 38 and match figures of 11 for 140, while Leach finished with five for 37. Only Dom Sibley (56) and Ben Foakes (20) offered prolonged resistance, but their fourth-wicket stand of 49 in 29 overs looked to have secured a draw before seven wickets fell for 14 runs at the end.

They claimed 21 points from the game to Surrey's five and closed the gap at the top of the table to just eight points with two matches to play.

The final day began with the sight of Banton limping slowly out to bat with a runner, as he had done the previous evening. After two balls, he had to drag his damaged ankle back to the pavilion again as rain interrupted play.

A resumption at 11.05am, with eight overs lost, saw Overton and Banton bring up a half-century partnership off 61 balls. The most extraordinary of Banton's six fours came when he reverse swept Shakib Al Hasan, despite severely limited foot movement.

The memorable 65-ball innings ended when Shakib found a way through Banton's defence and bowled him, leaving Overton one short of a deserved fifty, after facing 78 balls and occupying the crease for two hours and 16 minutes. Surrey were left with a tricky 13 overs to bat before lunch, but Rory Burns and Sibley negotiated it with skill and calmness. The pattern continued after another shower had delayed the restart until 1.20pm, with three more overs lost.

But as the effects of the roller began to wear off, the ball began to turn sharply and Vaughan struck a double blow in the 22nd over, having Burns caught behind for 15 and then bowling Ryan Patel for a third-ball duck. At the other end, Leach beat Ben Geddes with three successive deliveries in the 29th over.

Geddes' luck ran out in Leach's next over when he was pinned lbw and at 46 for three, Surrey were in a deepening hole. Sibley and Foakes abandoned any attacking intent and met the nagging accuracy of Somerset's spinners with a spell of solid defence, bringing 50 up in the 38th over.

Both were quick to make for the pavilion when rain started falling again at 2.45pm with the score 63 for three. Tea was taken with Sibley unbeaten on 38.

The final session began at 3.20pm with another three overs lost. Leach continued to probe and beat the outside edge, but after 44 consecutive overs of spin, teenager Vaughan took a break and was replaced by Craig Overton. Brett Randell then replaced Leach, who had sent down 14 maidens in 24 overs. After a few overs of seam, the spinners changed ends in a final Somerset throw of the dice, Leach switching to the River End.

A swept single off Vaughan took Sibley to a 165-ball half-century that perfectly suited the situation. But then Foakes edged Leach to Lewis Gregory at first slip and when Sibley's defiance ended in similar fashion in the left-armer's next over, panic set in for the visitors.

Gregory claimed a third slip catch to send back Shakib and give Vaughan his ninth wicket of the match. It became ten when Tom Curran aimed to cut the 18-year-old and got an inside edge onto his stumps.

Cameron Steel fell lbw to Vaughan and Surrey were eight down with a minimum of nine overs remaining. Jordan Clark and Kemar Roach ran down the overs with an obdurate partnership before Clark was bowled by Vaughan for a 47-ball duck.

Last man Dan Worrall came out to be surrounded by close fielders and lasted just two balls before Leach dismissed him leg before to spark wild celebrations among team-mates and supporters.