Another Munster mistake ended with a try under the posts for Guaillaume Bousses as Bourgoin regained the lead and referee Malcolm Changleng awarded Munster a penalty try after Bourgoin pulled down a rolling maul that looked certain to yield a try to send Munster in at the break leading 20-15.
O'Gara was wide with a long range penalty in the 44th minute but he found a huge touch four minutes later to gain Munster a foothold in Bourgoin's half but the 'home' side continued to benefit from Munster mistakes and when they lost a lineout close to their own line and then saw O'Gara's clearance blocked down they were fortunate not to concede a try.
That luck didn't hold out and in the 57th minute Nicolas Matthieu levelled with a score in the right hand corner.
Munster responded with the try of the game when Shaun Payne made the initial break before passing to Lifeimi Mafi who scored under the posts.
O'Gara pushed Munster ten clear with a penalty but Bourgoin roared back with a second try for Matthieu to ensure a nervous finale to the game.
Munster: S Payne; J Kelly (T O'Leary (70 mins), B Murphy, L Mafi, I Dowling; R O'Gara, P Stringer; M Horan F Pucciaiello 76 mins), F Sheahan (J Flannery 66 min), J Hayes; D O'Callaghan, P O'Connell capt; M O'Driscoll, D Wallace, D Leamy (A Foley 74 mins).
Bourgoin: F Denos; S Finau, G Bousses, R Coetzeei, Y David; S Laloo, M Parra; O Milloud, R Vigneaux, P Cardinali; B Williams, J Pierre; B Monzeglio, W Jooste, J Bonnaire capt.