Alastair Cook hit a century in a competitive match for the first time since his international retirement as Essex enjoyed a positive day against Kent.
Cook bowed out of Test cricket with an emotional 147 against India at The Oval last year but had struggled for consistency having returned to the Specsavers County Championship.
The 34-year-old began the red ball season with scores of 50, eight, 11, 0 not out, 31 and 40 not out, after crashing an unbeaten 150 against Cambridge MCCU.
But on his 100th first-class appearance for Essex, having made his debut in September 2003, he clocked up a typically gritty century to grind Kent down.
Cook ended up with 125 as Essex suffered a late collapse to reach 303 for eight at close on the first day at Chelmsford.
Kent captain Joe Denly, on his return to county cricket having been left out of England's World Cup squad, decided to put Essex into bat without a toss.
As the day wore on this proved a curious decision on a flat and well-paced wicket, albeit with the carrot on a stick for the bowlers of overcast conditions.
Left-handed batsman Cook chalked up 41 with Nick Browne for the opening wicket – the latter enjoying stroking Harry Podmore for two boundaries in the first over of the match.
But Browne looked uncomfortable against Darren Stevens, and duly fell victim to one that angled off his bat, with wicketkeeper Ollie Robinson taking the catch diving in front of first slip.
Tom Westley saw the score move on another 30 with Cook but flicked Matt Milnes to Stevens at short midwicket – the 43-year-old fielder stooping to grab an eye-catching low catch which belied his age.
Meanwhile, Cook was oppressive in his diligence to keep his wicket – scoring just four boundaries in his 128-ball 50.
On the rare occasions he attacked the ball Cook oozed quality, with trademark cuts and pulls, with 74 runs added with Dan Lawrence, before the latter was bowled by Milnes. That started a 130-stand with Ravi Bopara.
Cook moved to three figures with back-to-back boundaries off Denly – firstly cutting powerfully in front of square, before nonchalantly flicking a full-ball through mid-wicket.
The ton, which encompassed a mammoth 208 deliveries, was his first in the Championship since the 193 he notched against Middlesex in June 2017.
The milestones continued for England's greatest Test run scorer as he passed 23,000 runs in first-class matches when he reached 106.
Cook eventually departed in clumsy style, as Sean Dickson ran around from slip to square leg to run him out while attempting to come back for a second leg bye – it was the first time he had been run out in his Essex red ball career, having only been dismissed in that manner three times in his first class career.
Bopara and Ryan Ten Doeschate were both handed lives on 35 and one respectively, the former put down at first slip and the latter dropped by Podmore, who attempted a caught and bowled.
Bopara made hay by reaching his 54th first-class 50, made from 97 balls, but the Holland international did not as he steered Podmore to first slip to spark a collapse of three wickets for two runs in 17 balls.
Michael Pepper was caught behind and Bopara lbw, both to Stevens, before Peter Siddle nicked behind in the penultimate over of the day.
