However, the final scoreline relied on two late tries, the second coming in injury time at which point the Warriors were valiantly defending deep in Blues territory with just 13 players on the field. They had exhausted all their resources and had no-one to replace either Calum Forrester or Alastair Kellock when they retired injured with seven minutes still to be played.
In the last move of the match, Richard Mustoe ran in the bonus point try from 50 metres.
Nevertheless, it was a win that puts the Blues into third place in the Magners League table, four points off the leaders.
There may have been some head-scratching at the Liberty Stadium where Leinster were leading Ospreys a merry dance after their outstanding performer Isa Nacewa scored a 44th minute try to give his side a 15-12 lead against.
Leinster were full value for their advantage but it all went horribly wrong for them in a six minute period when they were reduced to 13 after Ed O'Donoghue and Ian Madigan were yellow carded and Ospreys were awarded the penalty try that separated the sides when David Wilkinson sounded the final whistle.
Munster's other Heineken Cup opponents London Irish (Toulon didn't play) were beaten 35-23 by Nothampton Saints at Franklin's Gardens where the home side blew the visitors away with a 24 point scoring burst in the second quarter.