Oliver Norburn’s fourth minute penalty - the first goal conceded by Town at Portman Road in the league this season - has given Shrewsbury a 1-0 half-time lead over the Blues.
Town were without top scorer Gwion Edwards and striker Oli Hawkins, manager Paul Lambert having revealed prior to the match that two unnamed players had picked up knocks in training during the week.
In total there were three changes from the team which lost 2-1 at Sunderland in Town’s most recent League One match 18 days ago.
In midfield, Brett McGavin came into the side for the suspended Andre Dozzell for his second league start and ex-Shrew Jon Nolan returned for Jack Lankester, who dropped to the bench, with Teddy Bishop the third midfielder.
Edwards’s place in the front three was taken by Freddie Sears, who was on the left, with Kayden Jackson continuing in the middle and Alan Judge on the right.
Tomas Holy was again in goal behind the same back four which faced the Black Cats, from the right, skipper Luke Chambers, Toto Nsiala, like Nolan facing his old club, Mark McGuinness and Stephen Ward.
James Norwood was on the bench having returned to training this week after suffering a minor hamstring problem in the FA Cup tie against Portsmouth alongside Luke Woolfenden.
The centre-half had missed the last three matches as he was self-isolating after coming into contact with someone who tested positive for Covid-19. James Wilson, a regular starter earlier in the season, was missing from the 18.
Shrewsbury, who went in to the game third bottom, were unchanged from last week’s 3-3 home draw with Swindon with former Blues trialist Shilow Tracey starting.
After both teams had taken the knee in support of Black Lives Matter, the game got under way with Shrewsbury going in front in only the fourth minute from the penalty spot, the first goal Town had conceded in the league at home this season and the Shrews’ first at Portman Road since 1957.
Shaun Whalley was played in behind on the right of the area by Norburn and McGuinness tripped him as he tried to avoid the Shrews forward running across his path. Referee Tim Robinson pointed straight to the spot and Norburn shot powerfully straight down the middle to beat Holy who got a touch on it.
After the early setback the Blues went about trying to get their passing out from the back going but struggled to impose themselves on the visitors. However, on eight Sears broke down the left and crossed low into Shrewsbury keeper Harry Burgoyne’s arms.
The early stages of the game were surprisingly open with both sides getting into promising positions around the opposition box, Shrewsbury more than the Blues. But in the 11th minute Jackson cut in from the left and hit a low shot which Burgoyne claimed without fanfare.
On 16 Shrewsbury thought they should have been awarded another penalty when McGuinness appeared to catch Marc Pugh as he cut inside him. Referee Robinson waved away the protests, despite the visitors appearing to have a strong case.
Town were forced into the first of their five available substitutions in the 22nd minute when Jack Lankester took over from Nolan, who had suffered what looked like a groin problem and following treatment on the pitch made his way around the perimeter to the dressing rooms.
Two minutes later, McGavin played a ball in to Judge, who flicked it in the path of Jackson but Burgoyne was quickly off his line to clear ahead of the striker.
The Blues gradually began to look more threatening and in the 29th minute Jackson fed Bishop on the edge of the box and the midfielder skipped into the box before hitting a shot to Burgoyne. Jackson may well have been better laying the ball off earlier to Lankester to the left.
Town claimed a penalty in the 32nd minute when McGavin’s low corner from the left was cleared against his own hand by Pugh. Referee Robinson wasn’t interested, however, the Blues were penalised in not dissimilar circumstances at Sunderland recently. Two minutes later, Norburn was booked for a foul on Bishop.
Jackson almost created a leveller in the 39th minute when he chased a McGavin pass to the byline on the right and cut it back. Lankester’s initial shot was blocked and the ball ran to Sears who seemed destined to score but his effort was diverted behind.
From the resultant corner Nsiala was pushed as the ball came across but referee Robinson again showed no interest.
That was the last serious action of a disappointing half from the Blues. Having got their early lead from a somewhat gifted penalty, the Shrews had looked the more dangerous side and might well have been awarded a second spot-kick.
Town, defending a 100 per cent home league record, had started to look more dominant the longer the half went on, although without creating too many chances. The double opportunity when Lankester and Sears had efforts blocked was the nearest they came to a goal, although the Blues will feel they ought to have been awarded a penalty for the handball.
Town: Holy, Chambers (c), Nsiala, McGuinness, Ward, McGavin, Nolan (Lankester 22), Bishop, Judge, Jackson, Sears. Subs: Cornell, Woolfenden, Kenlock, Huws, Bennetts, Norwood.
Shrewsbury: Burgoyne, Millar, Williams, Ebanks-Landell, Pierre, Daniels, Edwards, Norburn (c), Whalley, Tracey, Pugh. Subs: Iliev, Vela, Walker, Barnett, Udoh, High, Cummings. Referee: Tim Robinson (West Sussex).