Dawid Malan's second century of the season allowed Middlesex to turn the Division Two form book on its head with a three-wicket victory over Sussex.
Resuming on 122-5 at the start of the final day in pursuit of a target of 243, Malan advanced from his overnight position of 56 to finish unbeaten on exactly 100 as Middlesex secured their first win of the season shortly after lunch.
The left-hander, who hit 15 fours during his 173-ball effort, was well supported by Gareth Berg during a sixth-wicket stand of 127.
Berg fell lbw to medium pacer Robin Martin-Jenkins (4-46) one short of a half-century with 38 still required.
And seamer James Anyon (1-12) accounted for Tom Smith (8) to reduce Middlesex to 222-7 before Tim Murtagh (9no) joined Malan to finish the job in the fourth over of the afternoon session.
Despite suffering their first defeat of the campaign following four straight wins, Sussex remain well clear at the top of Division Two, while Middlesex climb off the bottom above Surrey after snapping a four-game losing streak.
Sussex's hopes of a fifth straight win in Division Two of the LV County Championship remain alive after Andrew Hodd led the a home fightback against Middlesex at Hove.
Having had Sussex four down overnight and with only a slender lead of 34, the visitors were the side in the ascendancy at the start of the third morning.
Their victory hopes were raised even further when England's Matt Prior fell early to Iain O'Brien for 49, leaving the score at 118 for five.
However Hodd made sure Sussex - who had suffered a top-order collapse on day two - did not roll over, making 109 to steer his side to a final total of 321.
The wicketkeeper-batsman shared two crucial stands worth 65, firstly with James Anyon (19) and then with Monty Panesar, who ended up unbeaten on 46 from 105 balls.
Left chasing a challenging target of 243, Middlesex lost early wickets - including stand-in skipper Andrew Strauss for 23 - to the seam duo of Corey Collymore and Robin Martin-Jenkins.
However Dawid Malan hit 56 not out to take the score to 122 for five when stumps were drawn - meaning Middlesex will return on Saturday needing a further 121 runs to clinch their first four-day win of the summer.
Sussex's bid to make it five straight victories in Division Two of the LV County Championship was held up by a determined Middlesex side at Hove.
The visitors recovered from 89 for four in the morning session to make 296 in their first innings, giving them a useful lead of 79.
Neil Dexter led the recovery effort with a well compiled 80, sharing a fifth-wicket stand with wicketkeeper John Simpson (45) worth 108 in 35 overs.
Gareth Berg then followed up his three wickets with the ball on day one by hitting a rapid 60 that included three sixes and six fours. He took 22 off one over from Monty Panesar before falling leg before to the spinner.
Corey Collymore eventually polished off the Middlesex tail to finish with figures of five for 67, though Sussex found it tough going in erasing the deficit.
Former Surrey seamer Tim Murtagh struck twice as the home side lost three wickets for 11 runs following an opening stand of 33.
Carl Nash fell to Pedro Collins to leave the score on 89 for four but Matt Prior, fresh off a century in the first innings, eased his way to 48 not out to put his side into a slender 34-run lead by the close of play.
Matt Prior scored his first hundred for over a year in front of England captain Andrew Strauss as Sussex fought back well against Middlesex at Hove.
The England gloveman, overlooked for the ongoing ICC World Twenty in the Caribbean, proved his class with an unbeaten 123 in his side's first innings total of 217 at Hove.
Prior stuck 17 fours and brought up his 21st first-class century during a 49-run stand with Monty Panesar for the ninth wicket.
Opening bowler Tim Murtagh (3-32) and all-rounder Gareth Berg (3-45) did the brunt of the damage for bottom-placed Middlesex, who are looking to snap a run of four consecutive Division Two defeats.
In response, the visitors reached the close on 46-3 after West Indian paceman Corey Collymore struck twice in quick succession.
After Strauss fell for just 13, Collymore then dismissed Scott Newman (also 13) and Dawid Malan in the space of three balls to edge Sussex ahead.