Sussex 128 for 3 (Wells 52*) lead Middlesex 75 (Robinson 8-34) by 53 runs

"One hundred percent a potential England cricketer." That was the assessment of Chris Jordan when his fellow Sussex seamer Ollie Robinson was called up for England Lions last month. The best figures in the Championship this season, with Middlesex routed for 75, should only add to his reputation.

Robinson's 8 for 34 in 11 overs, based on unremitting accuracy and a modicum of seam movement both ways from an attacking length, ensured that Middlesex were accounted for in only 21.4 overs at Hove, one of the fastest capitulations in their history, and was followed by the presentation of his county cap in the tea interval.

That cap is richly deserved. Since joining Sussex after Yorkshire released him for bad timekeeping, he has clocked in with 213 first-class wickets. This season, he now has 48 Division Two wickets at 15.48, a tally second only to Durham's Chris Rushworth who has played three matches more.

"The cap came out of the blue," he said. "I just wanted to get upstairs and take my spikes off. I was overjoyed. Sussex gave me my chance and helped get me back on the map."

Initially regarded as a mercurial young cricketer capable of bursts of talent, at 25 he is now a day-in, day-out performer. Sussex, seeking to arrest a run of three successive defeats, the last of them an innings loss against Lancashire at Old Trafford when Robinson was on Lions duty, desperately needed his pick-me-up.

This is a must-win match for both counties. Strongly fancied in April, they are off the pace, even in a season when three counties will be promoted to aid divisional restructuring. Sussex, 53 ahead with seven wickets standing at the close, put the wobbles of 15 for 3 behind them thanks to a settling third-wicket stand of 113 between Luke Wells and Alex Carey, but their bowling is understrength and are not in the clear yet.

Robinson was on course to take all ten, having picking up the first eight wickets in nine overs, with no thoughts of taking a blow, after Middlesex had been put in following a delayed start at 2.30pm. Then, as Robinson was still chuntering to himself over a refused lbw decision against Toby Roland-Jones, the Middlesex batsman edged Tom Haines to second slip.

He had to settle for Sussex's best bowling figures at Hove since 1955 when Ted James took 9 for 60 and dented Yorkshire's Championship chances in the process.

England, of course, are rarely on the lookout for traditional county seamers, able to take advantage of a bit of sap in a superficially gleaming white deck. Most pressingly, it is top-order batsmen who are on their mind. On current trends, they will probably look at his batting average of 21 and offer him a go in the top four.

Robinson's career-best came on a bowlers' day as potential England batsmen failed across the country. Dom Sibley's duck for Warwickshire was the most notable in this litany of underachievement, but Middlesex managed a triple failure as Sam Robson, Nick Gubbins and Dawid Malan, either recent England batsmen or, in the case of Gubbins, still highly regarded, managed six runs between them.

He has shown a new ability to crank up his pace at times this season - perhaps around the mid-80s mph - but he had the intelligence to recognise that this was not one of those Hove days. On a pitch that did just enough, but did it often, he concentrated on a full and probing length, six of his wickets falling in the arc between wicketkeeper and gully, plus one bowled and one lbw. This was not a story about failing batting techniques in the middle of a T20 tournament, but a high-class bowling display.

He conceded only four boundaries, three of them squirted behind the wicket and the only blow of note a step-away clout over mid-on by the No. 11 Tim Murtagh during a last-wicket stand of 25, the highest of the innings. Middlesex must be sick of the sight of him: he picked up 10 wickets at Lord's earlier in the season and has 46 in five matches against them. "Everyone has their team," he said.

He was on a roll straight away when he took a wicket with his first ball as Robson's sculpted defensive push resulted in an edge to wicketkeeper Ben Brown. Gubbins fell to a fine diving catch at gully, one-handed to his left, by Haines, and Malan's defensive cover-up gave Brown a second catch.

He then cut one back to have Paul Stirling lbw and when Stevie Eskinazi, whose 24 was comfortably Middlesex's top score, edged to second slip, Robinson's squawk of delight would have been looked on approvingly by the seagulls perched on top of the old carpet shed; they too understand a little bit of creating terror.

He ran in down the hill, the sun on his back, as if he would never tire. James Harris delayed him for only two balls, John Simpson left with a nod of approval as one seamed to hit his off stump and Nathan Sowter, his final wicket, ensured him of a career-best.

It was easy to forget how reliant Sussex can be these days on Robinson. Such luminaries as Jordan, Jofra Archer and George Garton - not forgetting Tymal Mills (now out for the season) and Reece Topley who play only T20 - were all missing from their pace attack. Mir Hamza, the Pakistan left-arm quick, has also now departed.

That left Haines as a make-do third seamer for the first time in his career; Jared Warner, on loan from Yorkshire, and a debutant slow left-armer, Elliott Hooper, never got on to bowl. Had Robinson had an off-day, it might have been a very different story, but these days he carries the responsibility confidently.