Birmingham's hopes of sealing an Elite League play-off place were put on hold as they went down to a narrow 47-43 defeat at neighbours Coventry.
Just 24 hours after Thursday's 56-34 home win over Eastbourne, the Brummies put up a valiant effort at Brandon but had to be content with a point.
It could yet be all-important, setting up Monday's home clash with Poole.
Coventry trailed by six points with just three heats to go, before winning a thrilling final heat climax.
Scott Nicholls and Chris Harris rolled back the years to see the Bees home, both overhauling Brummies' No.1 Bjarne Pedersen.
That leaves the Brummies agonisingly short of confirming play-off qualification, as Lakeside claimed maximum points against Peterborough.
Pedersen joint top scored for the men from Perry Barr, along with skipper Danny King.
But the Brummies felt the absences of Josh Auty and Ben Barker. And Coventry had a trump card of their own at reserve, Michal Szczepaniak top-scoring.
Brummies remain third in the table, level on points wth Lakeside, with Peterborough two points further adrift.
If they avoid defeat at home to either Poole or Swindon next week, they will definitely make the play-offs.
Should the Brummies lose both meetings, they need to ensure that the aggregate margin of defeat does not drop them behind Lakeside on race points difference.
The Hammers have completed their fixtures and the Brummies currently have an advantage of 17 race points.
To further complicate matters, Brummies would still be safe with two defeats should Peterborough fail to take at least two points from away trips to Belle Vue and Coventry - the current bottom two clubs.