Worcestershire 100 for 5 (Murtagh 2-22) trail Middlesex 188 (Hollman 62, Helm 50*, Leach 3-58) by 88 runs
Bowlers held sway as wickets tumbled on day one of the LV = Insurance County Championship Division Two clash between Middlesex and Worcestershire at Merchant Taylors School.
Joe Leach (three for 58) and Dillon Pennington two for 41 routed Middlesex's top order as they were hustled out for 188, Luke Hollman 62 and Tom Helm 50 not out providing belated resistance.
However the hosts too prospered ball in hand, Tim Murtagh returning two for 22 as Worcestershire plummeted to 49 for 5 in reply before Ed Barnard's unbeaten 33 left honours even.
Leach and Pennington wasted little time giving Middlesex cause to question their decision to bat on winning the toss.
Sam Robson, a man with three first-class centuries at Merchant Taylors made only three before Leach uprooted his middle stump with a peach of an in-swinger.
Pennington then stepped forward with a well-directed bouncer which Mark Stoneman injudiciously chose to hook and skied the easiest of catches to Leach at mid-wicket.
His demise sparked a collapse as Jack Davies nicked Pennington through to Gareth Roderick and the recalled Robbie White lost his off-stump to almost no shot at all.
The home side then compounded their woes with a runout which wouldn't have been out of place in a Keystone Cops silent movie. Max Holden played a ball to fine-leg, turned for a second, but neither he or non-striker John Simpson made eye contact and crashed into each other meaning the former was run out.
Leach trapped Simpson lbw soon afterwards and when Toby Roland-Jones drove loosely at Charlie Morris after lunch the hosts were 93 for 7.
It could have been worse with Helm dropped first ball, but that scare survived he and young all-rounder Hollman provided the first resistance of the day.
Hollman, still only 21, underlined his growing maturity, driving crisply square of the wicket and taking on the short ball. Eight boundaries helped him to a third half-century of the season in 82 balls, while Helm recovered from his sketchy start to hit Josh Baker over mid-wicket for the only six of the day.
Baker struck back to bowl Hollman for 62, ending a stand of 83, but Helm got to his second first-class 50 in 74 balls before Worcestershire mopped up the tail.
With so few runs to defend Middlesex needed early wickets and skipper Murtagh was the man to oblige, having Ed Pollock caught behind before pinning Jake Libby lbw in his next over.
Inspired by his batting Helm then found the edge of Jack Haynes' bat to give Robson a simple catch, but the opener shelled another from the bowling of debutant Umesh Yadav to reprieve Brett D' Oliveira on nought.
Yadav quickly banished that memory castling Taylor Cornwall for his first wicket in Middlesex colours, and D' Oliveira failed to make the most of his reprieve, gloving a viciously lifting ball from Roland-Jones to Hollman in the gully to leave the visitors reeling.
But Barnard and Roderick raised a 50-stand in the day's dying embers to leave things delicately poised.