Referee Andy Hall rushed from the field to avoid angry home fans at the end of this fiery clash at Loftus Road, that ended with promotion for Crewe.
The Birmingham official red-carded Clarke Carlisle and Stephen Kelly in 15 second-half minutes to end QPR'S outside chance of automatic promotion, and with results going their way Crewe were left celebrating a place in Division One next season.
The play-offs now beckons for Rangers who are sure to face punishment from the FA after their supporters streamed onto the pitch in their hundreds at the final whistle.
QPR needed three points from this clash to maintain any hopes of avoiding the end of season lottery and they had the better of the first half.
On loan winger Kevin McLeod should have done better after good work from Paul Furlong and the same player forced keeper Clayton Ince into a save minutes later.
Steve Palmer and Richard Langley brought further saves from the Crewe keeper who was keeping his side in the game.
The match changed after the break when Carlisle clattered into Ince and was given a second caution.
It got worse 15 minutes later when Kelly caught substitute Steve Jones for his second yellow of the match.
With the home side reduced to nine men the away side pushed forward in search of victory.
QPR keeper Chris Day pulled off a point-blank save to deny Jones and when the same player had the ball in the net minutes later the offside flag came to QPR's rescue.
Crewe threw everything at the QPR in the final minutes with Rob Hulse and Steve Foster wasting chances and Jones saw an effort crash against the crossbar as the home side's goal lead a charmed life.
But it ended goaless guaranteeing Crewe's promotion and sealing a play-off spot for QPR.