Mohammad Abbas took a hat-trick against Middlesex to put Hampshire on course for a second straight LV= Insurance County Championship win.
The Pakistan fast bowler dismissed Max Holden and Nick Gubbins at the end of his first over and sent visiting captain Stevie Eskinazi back to the pavilion caught behind at the start of his next to seal a memorable treble.
Middlesex were eventually all out for 79 at the Ageas Bowl, with Abbas finishing with six for 11 before Sam Northeast's 99 not out saw Hampshire close with a 444-run lead.
Bob Willis Trophy holders Essex were facing up to a first home defeat in almost three years despite a fine innings by Dan Lawrence.
After Durham had added 111 more runs to their overnight total of 148 for eight, two early wickets put the domestic champions on the back foot.
England batsman Lawrence responded with 76 but his dismissal sparked another collapse and Essex only had a lead of 45 runs with four second-innings wickets in hand.
Elsewhere in Group One, Dom Sibley added to England's injury woes after he was unable to bat for Warwickshire at Trent Bridge due to a fractured finger.
Without the opener, Nottinghamshire restricted the travelling party to 200 and 51 not out by Haseeb Hameed put the hosts in a strong position at the close.
Matt Critchley's three-wicket haul put Derbyshire on top at home to Worcestershire, who finished day two on 243 for seven, 147 runs behind.
England pair Ollie Pope and Ben Foakes hit half-centuries for Surrey, but they were still 122 runs behind Leicestershire's first-innings total in Group Two.
Pope, after a difficult series against India, returned to form with an unbeaten 92, while Foakes contributed 68 not in a 160-run stand to leave Surrey on 253 for three.
James Bracey pressed home his international chances with a sixth first-class hundred to put Gloucestershire on the verge of parity with Somerset.
The wicket-keeper was reserve for both of England's winter tours and hit 118 at Taunton as his team finished on 301 for eight in reply to 312.
Darren Stevens, one of Wisden's Cricketers of the Year, top scored for Kent with 52 but it was Yorkshire who took control of their Group Three fixture.
In front of England captain Joe Root, Zak Crawley fell for just one at Canterbury as the hosts were indebted to their 44-year-old veteran, who ensured they did not follow on, but the away side will aim to press home a 120-run lead on day three.
Stiaan Van Zyl's 113 was one of several notable scores for Sussex, who piled on the runs to finish on 481 for nine at Glamorgan, although George Garton fell three short of a century.
