All-rounder Ed Barnard marked his LV = County Championship debut by claiming his first wicket as the Worcestershire seamers struck back with a vengeance in the final part of a truncated day against Hampshire at the Ageas Bowl.
The England Under-19 all-rounder struck in the 40th over after skipper Daryl Mitchell had put Hampshire into bat under cloudy skies when play got underway at 3pm.
Then Jack Shantry dismissed Michael Carberry and Joe Leach sent back Jimmy Adams and nightwatchman James Tomlinson respectively as Hampshire finished on 119-4 from 51 overs.
It meant they had lost four wickets for 31 runs in the space of 11 overs.
Barnard ended an opening stand of 88 between Jimmy Adams and Liam Dawson by having the latter caught low down at second slip by Mitchell for 39.
Then Shantry was rewarded with the wicket of Michael Carberry (14) who tried to get the bat out of the way of a delivery and nicked it through to keeper Ben Cox.
Leach got in on the act by trapping Adams lbw for 48 before nightwatchman Tomlinson (5) fell in the same manner.
The Worcestershire attack plugged away all day and bowled tightly and accurately but for no tangible reward until their late quadruple breakthrough.
Leach had a confident appeal against Carberry for a catch behind by Cox turned down before the former England opener had scored but he failed to cash in.
Morning rain meant the loss of 45 overs before Hampshire launched their innings.
Charlie Morris and Leach shared the new ball, bowling seven and five over spells respectively, before being replaced by Shantry and Barnard.
They also bowled accurately but for no reward as Adams scored 27 not out and Dawson 24 not out in reaching 56-0 off 26 overs by tea.
Morris and Leach came back into the attack at the start of the final session but Adams and Dawson continued to bat carefully at a little over two runs an over until Barnard broke through and started a procession of wickets.
Colin Munro, Barnard and Joe Clarke all were all handed their first Championship starts and for the latter pair it was also their maiden first class appearances for the county.
Munro, who is primarily the county's NatWest T20 Blast overseas player for the second successive summer, was drafted into the side in place of Sri Lankan spinner Sachithra Senanayake.
Wicket-keeper Clarke, who is playing as a batsman, and all-rounder Barnard replaced Alexei Kervezee and Ross Whiteley respectively.
Munro played the first match of his second spell back at the club in Friday's T20 Blast win over Leicestershire Foxes at New Road.
The New Zealander has enjoyed a successful winter playing four-day cricket for Auckland and scored 899 runs including a career best 281 against Central District in his last first class innings on March 24 in Napier.
It means Senanayake has played the last game of his current spell with the club and will fly back to Sri Lanka to prepare for the ODI series with Pakistan.
He has played in the opening five Championship matches and collected nine wickets with a best haul of four wickets in the second innings against Sussex at Hove.
Saaed Ajmal is due to start his third spell at New Road when he flies in from Pakistan on Tuesday.
Munro admits that his approach to four-day cricket is similar to the white ball game.
The 28-year-old said: "I don't really see much change in playing one-day cricket to four-day cricket.
"Depending on the match situation, I just try and play to my strengths and that is 'hit ball, hit ball' and sometimes it works, sometimes it doesn't.
"I can look horrible in four-day cricket and still get away with getting decent scores. I'll play and miss a lot and I could go out and nick first ball.
"I don't try and go out there and leave balls and play the traditional Test match way where you are leaving balls and you are letting the bowler come to you.
"Looking to hit a boundary first is my number one (aim) and if I can't, at least trying to get off the mark."
Barnard has already played in the tour game against New Zealand and the opening two T20 Blast matches with Birmingham Bears and Leicestershire Foxes.
Clarke has earned his chance after scoring a double hundred for the Seconds against Gloucestershire at Cheltenham on Tuesday which was his 19th birthday.
Worcestershire: Mitchell*, Oliver, Fell, Gidman, Munro, Clarke, Cox+, Leach, Barnard, Shantry, Morris.
Persistent rain meant an early lunch was taken at 12.30pm before conditions improved sufficiently for the umpires to decide play could finally commence between the two promoted sides from last season.