Newcastle's assistant manager, John Carver, sprinted on to the pitch after the final whistle to confront the referee, Rob Styles, after his side had been deprived of victory by a stoppage-time equaliser.
Gary Speed had scored what looked likely to prove the winner with a superb strike in the first half, but Newcastle's advantage was cancelled out by Stern John, the substitute earning Birmingham City a deserved point by sliding in at the far post to beat Shay Given.
Some of Styles' decisions in the build-up to the goal had exasperated the Newcastle bench and in particular Carver, who was led away from the referee by Birmingham's Robbie Savage.
When Styles let Savage escape without punishment after a cynical, late challenge on Olivier Bernard, it almost seemed that he had seen the pre-match stat sheet which named him as the most card-happy referee in the division. But then Bernard found himself in the referee's notebook for an innocuous foul on Damien Johnson.
The Newcastle manager, Bobby Robson, singled out the decision which led to the equaliser for most criticism. Craig Bellamy, on his return from a lengthy lay-off with a knee injury, was pulled up for fouling Kenny Cunningham and, when Newcastle players protested, Styles moved the free-kick forward 10 yards. John then scrambled the ball home from the restart. Robson was particularly critical of Styles' original decision, saying: "How can a player receiving the ball foul a player behind him?"
But Robson admitted Birmingham's performance had been worthy of a point. "I think all in all it was about right for Birmingham to get something out of it, although we did have the game won with five minutes to go. I'm really disappointed about that. I'm angry that we've lost two points at a critical stage against a team also chasing the fourth spot."
Newcastle had taken the lead through a wonder goal from Speed. The midfielder received Darren Ambrose's pass and let fly from 30 yards, giving Maik Taylor, Birmingham's goalkeeper, no chance.
Steve Bruce, Robson's opposite number and a lifelong Newcastle fan, refuses to believe a Champions' League spot is a possibility for the men from the Midlands. He knows his squad still need improving, and despite having failed so far to persuade Nicky Butt to leave Manchester United, he still hopes to persuade the England midfielder to move to the Midlands in summer.
Bruce does expect to complete the £1.5 million signing for the Blackburn defender Martin Taylor before the transfer window closes. If Taylor's move goes through, he will join a squad brimming with confidence, which they displayed by taking the game to Newcastle.
They were rewarded by creating the best chances. Mikael Forssell missed poorly from six yards and Stan Lazaridis put the ball over the bar after Forssell had crossed in the first half. Birmingham then hit the bar after the break through Bryan Hughes, but Johnson wasted a gilt-edged chance. Clinton Morrison chased a poor header back and after a challenge with Given the ball fell for Johnson, who missed with a lob.
Thankfully for Johnson, his team-mate John, frustrated at not making the starting line-up, came off the bench and did a better job right at the last moment.
Birmingham City 1
Newcastle United 1
Half-time: 0-1 Attendance: 29,513Reuse content