Wells failed by only three runs to complete a sequence, quite possibly unprecedented, of three double hundreds in four innings, but between he and Millns Leicestershire were helped to a daunting lead of 291, which left Essex with no realistic ambitions beyond a draw.
It seemed within their scope to survive on a placid pitch offering only a modest degree of slow turn, even with a day and a half remaining, but two wickets in the last 45 minutes then tipped the balance in Leicestershire's favour.
A catch skied to mid-wicket off the left-arm spin of Matthew Brimson ended the threat posed by Stuart Law and then, still more vitally, Graham Gooch fell to a splendid off-cutter from Gordon Parsons 10 minutes from stumps.
Gooch, having raced to a half- century in 78 balls, changed tack completely after surviving a sharp chance to mid-wicket, dropping anchor to the extent that his next 22 runs took up 89 deliveries. But his dismissal leaves Essex, still 98 adrift, vulnerable should they suffer early setbacks tomorrow.
Wells had begun his run with 200 against Yorkshire in Leicestershire's last Championship game and, after failing in the Sunday league against the same opponents, followed that with 201 off the Berkshire attack in the NatWest Trophy. In fairness, the days when he was a medium pacer who could bat a bit are long gone. Jack Birkenshaw, the Leicestershire manager who persuaded him north in 1992, always had more regard for him than that but it is doubtful even he imagined such a story as the last couple of weeks has revealed.
It has all come about since Wells was obliged to retrain as an opener, a function he has performed on Sundays for a couple of seasons but which he has been forced by circumstance to adapt for first-class matches also. Considering what had gone before, to be out so close to another double hundred seemed something of a let-down, especially after the confident manner in which he had hit the England discard Ronnie Irani out of the attack. However, when the milestone loomed again, patience eluded him. In one of several attempts to reach it with a flourish, he tried to chop away a Steve Andrew ball that was too close to his body for the shot he intended and was left aghast as the ball deflected on to his leg stump off an inside edge.
Millns, having reached 51 on Friday, had been doing more than simply keeping the other end intact. Batting sensibly throughout, the one-time England aspirant took the opportunity to demonstrate an exemplary driving technique. Square-cutting Ashley Cowan for four, he overtook his previous best, 73, made against Lancashire this season.
On 97, Peter Such, his former team-mate, supplied a leg-side long hop which Millns ecstatically whipped away for his 13th boundary - and the 12th first-class century for Leicestershire this summer.Reuse content