Worcestershire claimed maximum bowling points, and then Ed Barnard and Gareth Roderick led a fightback with the bat as 15 wickets fell on the opening day of the LV=Insurance County Championship match with Middlesex at Merchant Taylor’s School.
They bowled out the home side for 188 in 59.1 overs on the stroke of tea in red hot weather.
It was a disciplined performance on a pitch offering some lateral movement and variable bounce.
Joe Leach added three more wickets after his eight in the game against Glamorgan, and his new ball partner, Charlie Morris, bowled accurately and tightly throughout.
Dillon Pennington caused problems, particularly during his morning spell; Barnard was a threat throughout, while spinner Josh Baker gained deserved late reward for his efforts.
Only Luke Holden and Tom Helm, who both made half-centuries, offered much resistance during an eighth-wicket partnership of 83.
Worcestershire also found batting a significant challenge in the testing conditions and lost half of their side for 49.
But then Barnard and Roderick dug in and also put away the loose deliveries during an unbroken half-century stand in steering Worcestershire to 100-5 from 36 overs.
Worcestershire welcomed back batter Jack Haynes after a three-week absence with a tweaked knee ligament and replaced Azhar Ali, who is on international duty with Pakistan.
The home side opted to bat but were immediately under pressure against the new ball attack of Leach and Morris on a wicket offering bounce and carry.
It was Leach who made the initial breakthrough with a superb delivery.
Sam Robson (3) pushed forward to a delivery that pitched, straightened, and knocked out the off stump.
Mark Stoneman and Jack Davies played and missed at excellent balls from Morris.
The home side reached 35-1 from 10 overs, but Pennington made two quick breakthroughs during an excellent first spell.
His second delivery accounted for Stoneman (18), who went to pull a delivery banged into the wicket, and he could only sky a catch to Leach at mid-wicket.
Davies (14) then tried to get his bat out of the way of delivery from Pennington but feathered a catch to keeper Gareth Roderick.
Pennington constantly beat the bat, but the next wicket fell to Barnard, who replaced Morris.
Robbie White (2) pushed half-forward and was bowled by the all-rounder.
Middlesex then were guilty of surrendering their fifth wicket when Max Holden (11) steered Pennington to third man.
He turned for a second run but collided with his teammate, John Simpson, and was run out by Baker’s throw to Roderick.
Leach came back into the attack and picked up the scalp of the experienced Simpson (7) lbw after he went around the wicket to the left-hander at 68-6.
Morris had a deserved breakthrough when he returned at the start of the afternoon session when Toby Roland-Jones (10) went for an expansive shot and was caught behind.
Helm on nought was dropped by Barnard at third slip off Pennington with the total on 94-7 and then produced staunch support for Hollman.
The pair brought up a half-century stand in 90 balls, and Hollman’s fifty came from 82 deliveries with eight boundaries.
Spin was introduced for the first time via Baker in the 42nd over.
Hollman on 54 survived a difficult stumping chance when the ball bounced up sharply after he came out of his crease to Baker.
But he added only eight more before pushing forward to Baker and having his off bail removed after a stand of 83 with Helm.
Umesh Yadav (0) aimed a huge hit at Leach, and Haynes running from first slip to third, clung onto a skier.
Helm completed the second 50 of his career before Baker wrapped up the innings by bowling Tim Murtagh (5)
Leach finished with figures of 14-3-59-3, Morris 11-4-25-1, Pennington 13-1-41-2, Barnard 13-3-34-1 and Baker 8.1-1-29-2.
When Worcestershire batted, it was a similar scenario with bowlers taking advantage of the helpful conditions.
Ed Pollock (8) was caught behind after driving at a delivery slanted across him by Murtagh, who then had Jake Libby (15) lbw to a ball angled in after he had hit three early boundaries.
Haynes (9) got off the mark with a boundary backward of square against Roland-Jones but then edged Helm and was caught at second slip.
Taylor Cornall battled away for 11 off 39 balls during a testing spell from Umesh Yadav before he lost his off stump to a pacey delivery from the Indian star.
Club Captain Brett D’Oliveira (5) then fell to an almost unplayable delivery of extra bounce from Roland-Jones, which he gloved to third slip.
Barnard and Roderick joined forces for the final hour of the day and tried to rebuild the innings in a similar fashion to Hollman and Helm earlier in the day.
Roderick leg glanced Yadav for his first boundary, and Barnard produced a series of superb cover drives, including successive fours off Helm.
The 50 partnership was completed off 91 balls in the final over of the day and, Barnard will resume on 33 from 48 balls with six fours and Roderick on 18 from 47 deliveries.