Josh Rymell's century the centrepiece as Essex trounce Yorkshire

Not since Dan Lawrence made such an impact in his first season in 2015 had a graduate of the Essex academy made a hundred for the county. That shortfall has now been addressed by two century-makers in this season's Royal London Cup - Feroze Khushi and now Josh Rymell, both of them encouraging hopes of a new dawn. But how to regard it? The challenge of this tournament is to distinguish the false dawn from the true.

Rymell's 121 from 130 balls was the centrepiece of Essex's trouncing of Yorkshire in the first RLC play-off - a 129-run victory that secured them a semi-final place against Glamorgan in Cardiff on Monday. For Yorkshire, the last six weeks of the season still bring hopes of success in the T20 Blast and Championship, although as far as four-day cricket is concerned they carry forward a considerable points deficit in to the final group stage.

When Lawrence became Essex's third-youngest Championship century-maker, taking Surrey for 161 at the age of 17, county cricket was still confident in its value and the feat gained considerable attention. Khushi and now Rymell have taken their chance in a much-devalued tournament, and not to recognise that 50-over cricket is now largely developmental is to abandon attempts at proper evaluation.

Nevertheless, with county debutants in List A cricket this season now well past the hundred mark, Essex's batting pair look more persuasive than many. Khushi failed on this occasion, George Hill's inswinger bowling him through a sizeable gate, but Rymell, who has been promoted from the middle order to opener as the tournament has progressed, produced an expertly-paced innings that belied his years. He now has 287 runs at 57.40, although he would have had considerably fewer has Dom Bess not dropped him off Hill on 36.

Bess was one of a handful of Yorkshire players who could confidently expect to get into a full-strength side, but he failed to produce the turn that Essex's spinners - the part-timer Tom Westley among them - found in reply. Yorkshire were routed by a trio of Essex spinners on a worn surface as they set sail for 318.

Their start was secure enough, as they reached 68 for 1 in the 15th over, but Will Fraine and Will Luxton fell to lofted legside hits in successive overs as Simon Harmer and Aron Nijjar enforced a grip that was never relinquished. In seven overs, they shared four wickets at a cost of 20 runs to leave Yorkshire reeling on 88 for 5. Westley then had Gary Ballance lbw on the back foot and picked up a three-for. The margin of defeat could have been much higher were it not for a spot of window dressing from Matthew Revis and Matthew Waite.

Yorkshire held Essex for much of their innings: Khushi was the third batter to fall at 108 in the 27th over and Paul Walter's scratching around thereafter told of an unrewarding season. But Mathew Pillans, a curio among Yorkshire signings, bowled Walter into form with five overs which went for 50.

Although Walter departed at mid-off to a leading edge against Revis, Essex added 141 from the last 83 balls. Rymell was motoring by then and found willing accomplices in Adam Wheater (34 from 20) and Harmer (31 not out from 13) as Yorkshire's bowling fell apart. Only Hill, who floated his medium-pace into the blockhole to good effect, and emerged with 3 for 51, came out with much credit. It was such a delivery that did for Rymell as he attempted a flat-batted scrape to third man.

Ballance, back in a captaincy role that has not always sat easily with him, suggested that Yorkshire had bowled well for the entire innings and that everybody would be much better for the experience. Which was nice, even if it did not stand up to scrutiny. Essex, meanwhile, are one game away from their first List A Final since 2008. That is even nicer. But maybe that doesn't stand up to much scrutiny either.