Sir Alastair Cook was once again the central figure as Essex and Somerset made their final bids to claim the inaugural Bob Willis Trophy on day five at Lord's.

The first-class season decider looked set for a tight finish with Somerset declaring early in the morning to leave the Chelmsford side needing 237 to win. At lunch they had moved to 61 for two, wearing a couple of losses as Cook (29no) and Dan Lawrence (15no) steered them to the break.

Essex hold an extra trump card with the knowledge that a drawn match would see them take their third red-ball title in four years, courtesy of their first-innings advantage.

That they held the potentially-decisive lead owed greatly to Cook, who hit a magnificent 172 on day three, and he was set to be the game's decisive figure after the first session. With every over he remains in position, Somerset's chances diminish and Essex's grasp grows.

He got off the mark with a graceful straight drive off his third ball of the day, slightly over-pitched by Josh Davey, but life was not entirely serene in the opening burst.

Davey's next ball whistled past the outside edge and he had a couple of worries in the teens, with a pair of big lbw shouts from Lewis Gregory and Craig Overton going in vain and a genuine play-and-miss at the latter.

There were five boundaries to his credit too, timing things typically well when the seamers strayed towards his pads. Gregory got his side into the contest with his second ball of the innings, Nick Browne (13) held by Tom Abell at third slip, while Overton made the most of the chance to attack a fresh batsmen, pinning Tom Westley lbw for a six-ball duck.

Lawrence helped Cook stem the tide, with the pair adding 35 before the break.

Somerset had earlier batted on for 8.1 overs, declaring on 272 for seven with Overton on 45 not out and allowing themselves 80 overs to push for 10 wickets.