Lyndon James and Steven Mullaney ride their luck to frustrate Essex once more

Recent history repeated itself as Steven Mullaney and Lyndon James proved thorns in Essex's side for the second time this season at Chelmsford, the pair's 117-run fourth-wicket partnership continuing on from the 123 they added in Nottinghamshire's innings victory at Trent Bridge in the reverse fixture.

Today's effort came at a pace more akin to red-ball cricket - 52 overs as opposed 30.3 - but just as before, both made half-centuries. Shortly thereafter, they both fell guiding balls to Alastair Cook at slip in quick succession, as if a long-time married couple dying of broken hearts.

Joe Clarke too passed fifty, having earlier retired not out. He returned with a flurry of six boundaries in 21 balls off Peter Siddle, playing "downright beautifully" as one independent observer noted and finishing unbeaten on 57. It meant Notts, closing on 248 for 6, have laid solid foundations in a game that looks set to be a top-of-the table slow burner.

There was also some excitement of an unusual kind for the locals, a decent proportion of whom reached the obligatory shade of scarlet by close. And it wasn't just the rare sight of Paul Walter and Ryan ten Doeschate operating in tandem shortly before tea.

Walter - a giant left-arm allrounder who bats more than he bowls these days - first struck James' helmet with a ball that rose sharply. After receiving treatment, the batter continued. An over later, umpire Ian Blackwell proposed a conscious uncoupling of bowler and ball after Walter released his second beamer. Both were accidental, one each at James and Mullaney, and he had the grace to offend with the first ball of his over, ensuring an unblemished scorecard. An 'I was there' moment for the 600 who passed through the gates? Maybe not, but at least that many were allowed as part of a pilot event: tomorrow, it's back to 200.

Electing to bat, Nottinghamshire's top-order Bens, Slater and Compton, traded early boundaries. But having taken 25 from the game's first 3.3 overs, Compton nicked Siddle to slip. Two runs later, he trapped a third Ben - Duckett - in front, though he didn't much like the decision. Slater then took a shine to Shane Snater, three boundaries coming in quick succession. But bounding in from an odd angle to come around the wicket - Snater got revenge removing Slater lbw. Again, the decision appeared to come as a surprise.

Out came a long-sleeved James at 48 for 3, who, having limbered up as if about to pole vault, was nearly heading straight back from whence he came. A vociferous lbw appeal was turned down but when Clarke took a blow on the bottom hand from Sam Cook and was forced off, Essex sensed a collapse.

James and Mullaney had other ideas, not that they found it easy. James struggled early, chipping a rare Harmer full toss just shy of Cook at mid-off. He later nicked between Harmer and Nick Browne, socially distancing at second slip and gully as Siddle let out an anguished cry.

But there were some nice strokes too, a glorious checked on-drive off Siddle the pick of them. An outside edge moved him to 49, and his fourth half-century of the summer came from 145 balls. Shortly after tea, he finally fell victim to Siddle who had worked him over all day.

Mullaney is one of those players who always seems to make runs, although he should have been mulling over a disappointing effort. He had made four when Alastair Cook shelled a sharp catch at first slip, and six when the ball popped out of a diving Nick Browne's hands. Browne appeared to have clung on at cover, but landing on the matting protecting next week's T20 pitch proved fatal.

It was an unusually reserved knock, a pulled boundary off Sam Cook eventually taking him into double figures after 62 balls, but it was needfully responsible, and he still managed the only six of the day when Harmer dropped short.

In the evening sunshine, Cook returned to bowl a fine new-ball spell, the wicket of Tom Moores just reward for 23 overs of toil. Harmer, though, went wicketless, his drought now extending beyond 73 overs.

With the stakes high for the defending champions, it seemed odd that Jamie Porter was rotated out of their side. The logic was sound, Snater having claimed a career-best 7 for 89 at Trent Bridge last month, but after a mixed season (10 wickets at a cost of 51.30 in his first six games), Porter returned to form with seven wickets at Chester-le-Street last week - and Essex's next four-day game is not until July.

True, they started five points ahead of Nottinghamshire in second, but they have played one more game. And should these teams qualify as top two, they would each carry through half the points earned off the other into September's top division. The onus, then, is on Essex to force a result - much for Tom Westley to ponder tonight.