Unfaniced Connacht pulled off a huge shock as they beat reigning champions Leinster 26-23 in Dublin in the Celtic League.
That made it two defeats in a row for the Dubliners, who saw former outside half Mark McHugh kick them to defeat with an injury time drop goal.
Having opened their Celtic League campaign with a win over Borders in SDcoytland an dthen a home win against Cardiff, this was the best of the lot for the west coast men.
Tries by scrum half Chris Keane in the first half and wing Wayne Munn in the second allowed Connacht to notch a famous victory.
Leinster's Irish back row man Keith Gleeson helped himself to two tries, the second of which helped to level the scores after an hour, but the better team won in the end.
Former Irish outside half Eric Elwood chipped in with three penalties and two conversions, although it was McHugh's drop goal that ultimately grabbed the glory.
Munster had Lions centre Rob Henderson to thank for their last gasp victory in Edinburgh, where they beat the previously undefeated home side 28-21.
Jeremy Staunton kept Munster in touch with seven penalties before Henserson crept over for the vital try.
Staunton's conversion added the extra points and Edinburgh were left dreaming of what might have been having scored two tries through Derrick Lee and Chris Paterson.
Munster now lead Pool A, with Connacht in charge in Pool B.
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