Alastair Cook rediscovered the sort of imperious form that had eluded him this season, but fell four runs short of the 63rd first-class century of his career on the first day of the day-night match at Chelmsford.

The former England captain, on 96, looked to be attempting to reach three-figures for the first time in the Specsavers County Championship for a year with one shot. He went to whip Dom Bess through midwicket off the 165th ball he had faced, missed and was trapped lbw.

The indefatigable Bess bowled unchanged from the River End at The Cloudfm County Ground from the 20th over to the 88th, and finished the first day with figures of 35-7-74-2. Essex ended a swelteringly hot day on 298 for four from 98 overs.

Cook had appeared unflappable in taking his season’s Championship total to 409 runs at an average just over 51. He hit 15 fours, driving in the ‘v’ between mid-on and mid-off and dismissing anything short with a firm pull.

He put on 151 for the first wicket with Nick Browne – by 40 runs the largest stand for any Essex wicket in the Championship this season, and 93 better than anything by any combination of openers.

It revived memories of Essex’s inaugural day-night Championship match a year ago when Cook and Browne posted a county-record 373 stand against Middlesex, and Cook scored his last four-day century for the county.

The partnership had been together for more than 48 overs when Cook smashed Timm Groenewald firmly back at the bowler who deflected the ball on to the wicket to catch Browne out of his ground. Browne, returning for his first game since the beginning of May after breaking a finger, had hit 11 fours in his 142-ball 66.

Cook’s dismissal brought in Michael Pepper for his first-class debut on his 20th birthday. The wicketkeeper-batsman has scored a stack of runs in the 2nd XI this season.

Tom Westley had been playing comfortably for his 21 from 46 balls when he drove Gregory uppishly to short cover.

Apart from a series of short balls early on, Pepper looked untroubled in reaching 22 until he was bowled by Bess.