Jack Leach returns for one of the most important matches in Somerset's history when leaders Essex visit Taunton for the Specsavers County Championship title decider, starting on Monday.

The hosts must win to secure the pennant for the first time. They go into the match 12 points adrift in second place, but optimistic of making home advantage tell, having won five and drawn one of their six Championship games at the Cooper Associates County Ground this season.

Leach's availability after his Ashes heroics is a major boost. The left-arm spinner, who has just been awarded an England incremental contract, trained with the squad on Friday and could prove a key figure on a pitch sure to turn as the match progresses.

With rain forecast, Somerset will be keen to play on a result wicket in the hope of forcing a victory well inside four days. A gamble on a bowler-friendly surface appears to offer their best chance, even though Essex have two of the most prolific wicket-takers in the Championship.

Off-spinner Simon Harmer is top of the list with 78 wickets, while seamer Jamie Porter is also in the top 10, with 48.

Somerset head coach Jason Kerr is in confident mood, despite last week's 136-run defeat by Hampshire at the Ageas Bowl.

"It's an incredibly exciting week ahead, not just for the players, but for the many supporters, who have taken the emotional journey with us in recent weeks," he said. "What could be better than the two best teams in the Championship going head-to-head with the title as the prize.

"We cannot control the weather, but I believe there will be enough play to achieve a decisive result and we back ourselves against anyone on our home pitch."

"Essex have had the distraction of Vitality Blast Finals Day this weekend and hopefully we can capitalise on that" Somerset head coach Jason Kerr

A packed crowd and large media circus will descend on the County Ground, most of the latter expecting Essex to be crowned champions.

Kerr acknowledges that Somerset's batsmen will need to raise their game. None of them is averaging more than 33 in the competition this season, whereas Essex have three with an average of more than 40 in Sir Alastair Cook, Ravi Bopara and Dan Lawrence.

"Statistically, our batting looks poor, but we have played on some tough pitches and there have been some fine innings in difficult circumstances that have helped us win through," said Kerr.

"I am expecting the players concerned to step up on last week when we came across a bowler in exceptional form. Kyle Abbott's performance was just incredible."

After discussions with director of cricket Andy Hurry and skipper Tom Abell, Kerr looks set to stick with the same batting line-up against Essex, with Leach's inclusion likely to be the only team change.

Jamie Overton missed the Hampshire match with a back injury and was sent for a scan on Friday. He was already facing surgery on an ankle spur at the end of the season.

Kerr's final message to the Somerset players will be to "go out and enjoy the occasion". While he accepts there is pressure to deliver that elusive first title, he wants his team to ignore the hype as much as possible.

"So much work has gone into getting us this far," he said. "Now it is important we stick to the processes which have put us in the top two.

"Essex have had the distraction of Vitality Blast Finals Day this weekend and hopefully we can capitalise on that. Given a reasonable amount of luck with the weather, I'm sure we can do it."

Kerr ruled out a sentimental recall for Marcus Trescothick, who announced some time ago that this would be his final season as a player. Somerset will make a presentation to the 43-year-old at the lunch interval on Monday to mark his 27 seasons of service.

Trescothick will be in and around the dressing room during the game and Kerr said: "I hope he gets around the ground and soaks up the atmosphere. It would be fitting if we could win the title he has dreamt about for so long."