Middlesex are facing a fight to save their LV= County Championship match against Durham after day two at Chester-le-Street.
Already in deep trouble after Durham made 411/4 after being inserted by captain Chris Rogers on the first day, table-topping Middlesex were unable to stop the deluge of runs on the second morning, as Scott Borthwick made the first double-century of his career.
All-rounder Borthwick, who has hopes of making England's team for the first Test of the summer against Sri Lanka at Lord's on 12 June, resumed on 164, and soon set about adding to what was already his highest first-class score.
Middlesex's attack, so strong thus far this season, were dismantled as Tim Murtagh, Steven Finn, Toby Roland-Jones and Ravi Patel all concded over 100 runs.
Only Roland-Jones emerged with any credit as he picked up his third five-wicket haul in succession, eventually ending with figures of 5/103.
Even after Borthwick was dismissed for 216 the hosts continued to assert their dominance, as debutant Jon Hastings bludgeoned 38 off 25 balls as Durham declared on 568/9.
In reply, and faced with a huge follow-on target of 419, Middlesex collapsed to a score of 69/4 to compound their misery, with Rogers (1), Dawid Malan (10), Neil Dexter (3) and Sam Robson (24) all falling cheaply.
Only five balls were able to be bowled after tea due to rain, and Middlesex will be hoping for more inclement weather over the next two days if they are to save this match.