Tom Haines and James Coles both scored centuries as Sussex clinched the second division title on a day of celebrations at Hove.
Haines made 105 – his third hundred of the season – and Coles hit an unbeaten 132 as Sussex finished the season undefeated at the 1st Central County Ground after drawing with Middlesex.
They began the final day on 112-2, needing to reach 250 and a fourth bonus point to ensure promotion as champions.
There was a slight sense of anti-climax shortly after lunch when Luke Hollman overstepped and the two no balls took Sussex to 250.
But the celebrations out in the middle, where Coles and skipper John Simpson embraced warmly, and on the pavilion balcony showed what it meant as Sussex returned to Division One after a nine-year absence.
Sussex finished 20 points clear of Yorkshire, having won eight of their 14 games.
There had still been a bit of work to do at the start before the celebrations could begin – and Haines and Tom Alsop settled any nerves by putting on 123 in 35 overs for the third wicket with few alarms.
Alsop passed fifty for the eighth time this season and must have fancied his chances of converting it into a first hundred, only to mistime a pull off Josh De Caires to deep mid-wicket.
Haines reached a chanceless hundred – the 12th of his career – with a cut through backward point off Hollman for his 13th boundary only to fall just before lunch when he bottom-edged into his stumps to reward Hollman’s perseverance.
Once Sussex had achieved their objective, the cricket not surprisingly lost any intensity. Ryan Higgins bowled off breaks instead of his usual medium-fast seamers, Luis du Plooy gave his left-arm tweakers an airing as Middlesex employed nine bowlers including Mark Stoneman, who sent down seven overs in his final game for the county, and wicketkeeper Jack Davies.
Not that Coles or Simpson were complaining too much as they built a fifth-wicket stand of 226 in 46 overs, beating the previous best against Middlesex of 223 set by Simpson and Cheteshwar Pujara when the teams drew at Lord’s earlier in the season.
Coles played aggressively, hitting six sixes and nine boundaries, clipping Hollman into the leg side to bring up his first hundred of the season.
His unbeaten 132 came from just 150 balls while Simpson took his aggregate to 1,197 runs at 74.81 with an undefeated 87.
It was fitting that Simpson, whose five centuries as well as his leadership have been so crucial to Sussex’s success, was there when the players shook hands at 4.20pm with Sussex on 459-4.
A few minutes later the celebrations could begin in earnest when the trophy was presented to him by another former Sussex captain, Clare Connor, the managing director of England Women’s Cricket.
Sussex head coach Paul Farbrace said: “Last year we put down some good foundations. We had our disciplinary issues and that cost us points as did our poor over rate. We got the same number of points as Worcestershire but I didn’t feel we weren’t ready to go up.
Well done chaps