Dominic Solanke and Jaidon Anthony showed Bournemouth boss Scott Parker there is life without wantaway striker Arnaut Danjuma after hitting late goals to claim a 2-0 win at Birmingham.
With last season's fellow joint-top scorer Danjuma reportedly on the verge of sealing a move to Europa League winners Villarreal, Solanke's classy 77th-minute finish put the Cherries ahead.
Former Arsenal trainee Anthony, 21, sealed the points by hooking home Bournemouth's second after 87 minutes for his first professional goal.
Defeat was harsh on Birmingham, who had looked set for a fourth successive clean sheet and, indeed, created the better chances before Bournemouth's late rally.
But Lee Bowyer's side were left to rue missed chances as a Lukas Jutkiewicz header was ruled offside while Cherries keeper Mark Travers made three good saves.
However, despite missing the suspended David Brooks - sent off in Saturday's win at Nottingham Forest - and Danjuma, the visitors found a way to record back-to-back away victories for Parker.
Blues, again playing in front of a vastly reduced crowd - 9,922 - with two sides of St Andrew's awaiting safety certificates, began brightly with on-loan Manchester United man Tahith Chong prominent on his home debut.
The midfielder saw a 20-yard curler beaten away by Travers in only the second minute before slipping Jonathan Leko in for another shot parried by the Cherries goalkeeper a few minutes later.
Leko, on his first start of the season, and Chong, on his return from a minor knock that meant he missed Saturday's draw with Stoke, then saw goalbound efforts blocked and deflected respectively.
Bournemouth, who had been free-scoring with nine goals in their opening three league and cup matches, failed to register a single shot - on or off target - in the first half.
They remedied that within a minute of the start of the second period, Anthony latching on to Jordan Zemura's reverse pass to bend in a low strike that Matija Sarkic tipped wide for a corner.
Anthony curled straight at Sarkic from 20 yards before Birmingham had a goal chalked off just after the hour, Jutkiewicz adjudged offside as he looped home a header from Maxime Colin's cross.
That chance buoyed Blues and Travers had to be alert to foil a Marc Roberts header from a corner with Leko flagged offside as he tried to turn home the loose ball.
However, Solanke silenced St Andrew's 13 minutes from time, expertly holding off Roberts as he ran in from the right channel before steering an accurate finish across Sarkic into the far corner.
Zemura cleared a Jeremie Bela cross from almost on his goal-line to deny Blues an equaliser before Anthony pounced to hook home Zeno Ibsen Rossi's knockdown to seal the win.
What the managers said...
Birmingham's Lee Bowyer: "[Solanke's goal] was handball, he nudged it with his arm in front of him. It's disappointing because I think we deserved more than that. From start to finish, we made it difficult for them, they couldn't break us down - but the first half-chance they got, they scored. The first half, we did really well, we moved the ball better, created some good chances, we were winning the ball in great areas and everything was going to plan apart from getting a goal.
"The players gave everything, they can't do any more than they did. As a group we're improving all the time and we showed that again tonight because some of our play was excellent. If they give the handball, I don't think they score the second goal and I always feel we have a chance from a set-piece as we are a powerful side and might nick one."
Bournemouth's Scott Parker: "We're stretched at the moment but this group of young players have been nothing but first class. They have worked tirelessly the last eight to nine weeks and if you work hard, you reap rewards - they deserve to be sitting on seven points and they deserve two wins and a draw.
"A lot of these players are experiencing things for the first time in this league and they are doing a fantastic job. We're trying our hardest to bring players in but saying that the players that are here, in those roles, have done fantastic as well."