North End’s nine-game unbeaten run came to an end at St Andrews, As Garry Monk’s side scored three unanswered second half goals.
An early long-distance effort from Maikel Kieftenbeld, followed by efforts from Jacques Maghoma and Che Adams gave the home side the three points.
Manager Alex Neil was forced to make two changes to his starting XI, losing Ben Pearson and skipper Tom Clarke through injury, with Darnell Fisher and Ryan Ledson returning to the team. Ben Davies was fit to make the bench, whilst Jack Baxter was also included for the first time.
The first half was devoid of clear cut chances, however, it was the yellows who were the ones who tested their opposite keeper, with the experienced Lee Camp in the City goal twice needed to keep out the Lilywhites.
Just before the half hour mark was the closest the visitors came to a goal in the opening period; a Tom Barkhuizen long throw from the right recycled by Paul Gallagher and Louis Moult, with his back to goal on the edge of the area, executing a superb bicycle kick, that Camp tipped over the bar.
And the former Derby and Nottingham Forest stopper again needed to keep his wits about him just minutes later as a Gallagher free kick from the left was met by stand-in captain Paul Huntington, whose header was on target, but straight at the custodian.
But just 30 seconds into the second half North End went behind. A long ball over the top from Kieftenbeld went over the North End defence and through Declan Rudd into the goal.
Straight after it could have been two, with the Blues top scorer Lukas Jutkiewicz forcing the North End No.1 into a fine save to his right, after the keeper had pushed away Gary Gardner’s initial shot.
But it was 2-0 just after the hour mark. North End had reason to be incensed as Alan Browne was seemingly fouled in the middle of the pitch, but the referee let play go on and eventually the ball fell in the box to Maghoma, who turned and fired right footed into the bottom left-hand corner from 15 yards out.
Lukas Nmecha was brought on and he and Louis Moult combined well mid-way through the half, with the on loan striker firing a vicious effort from the left corner of the penalty area that flew past Camp, but just over the cross bar.
A Gallagher free kick on 73 minutes beat the wall, but flashed just past Camp’s outstretched right arm and the left-hand post, after Nmecha had been hauled down 25 yards from goal as the yellow tried to get back into the game.
But it was 3-0 when Adams broke down the left-hand side on a counter-attack, running onto Kieftenbeld’s lofted ball over the top, before getting into the area and firing right-footed into the bottom right corner of the goal.
Graham Burke was introduced and almost had an immediate impact, his shot blocked for a corner and then almost forcing Camp into a mistake as he tried to get on the end of Fisher’s long ball back into the box after Gallagher’s initial cross had been headed clear.
But the scoreline remained 3-0, with the home side extending their unbeaten home start to the season, ending the Lilywhites’ excellent run of results in the process.
Birmingham City line-up: Camp, Pedersen, Colin, Kieftenbeld, Mahoney (Harding, 74), Adams, Jutkiewicz (Bogle, 83), Dean, Maghoma, G Gardner, Morrison (c). Subs not used: Trueman, Roberts, C Gardner, Dacres-Cogley, Lakin.
PNE line-up: Rudd, Fisher, Earl (Hughes, 46), Ledson, Huntington (c), Storey, Barkhuizen, Gallagher, Moult, Browne (Burke, 79), Barker (Nmecha, 57). Subs not used: Maxwell, Davies, Woods, Baxter.
Attendance: 20,523 (1,258 PNE fans)
Referee: Mr D Webb