Connacht (6) 12
Pens: Keatley 4
Munster (3) 16
Try: Gleeson Con: O'Gara Pens: O'Gara 2 Drop: O'Gara
Connacht duo Niva Ta'auso and Erza Taylor tackle Munster's Tom Gleeson
Magners League leaders Munster withstood late pressure to edge out Connacht in Monday's clash at the Sportsground in Galway.
Ian Keatley's four penalties helped Connacht lead 12-6 after an hour but a fortunate Tom Gleeson try helped Munster take the verdict.
Niall Ronan's late sin-binning put Munster under pressure but Tony McGahan's side held on to win.
Stand-in captain Ronan O'Gara kicked Munster's other 11 points.
Munster's pack had to see out a series of injury-time scrums, five metres from their line, before Connacht's brave bid was ended by a turnover in the loose.
Suitably fired up for this derby, Connacht's clever use of the boot saw them build some promising phases in the visitors half.
An early aerial assault led to a first successful penalty from Keatley, who stood in at out-half for an ill Miah Nikora.
Ezra Taylor was penalised for bringing a maul down illegally, allowing O'Gara to kick Munster level four minutes later, but Connacht continued to force the issue.
Keatley restored his side's lead before the break although the Connacht fly-half and O'Gara missed penalty chances at either end.
Another Keatley penalty extended Connacht's advantage to 9-3 after Peter Borlase has transgressed in a ruck.
O'Gara responded to cut Connacht's lead to three points again but Munster then suffered a blow when Alan Quinlan was forced off by a seemingly serious elbow injury.
Keatley's fourth successful penalty put Connacht six clear again as a festive surprise appeared on the cards.
But then came Munster's all-important try 15 minutes from time.
Barry Murphy dropped a pass near the Connacht 22 but a favourable bounce saw him hack on twice before Gleeson reached out to dot down just before the end line.
O'Gara slotted a brilliant touchline conversion and his subsequent drop goal left four points between the teams.
The westerners produced intense late pressure with Darragh Fanning and man-of-the-match Sean Cronin to the fore.
Ronan was sin-binned for killing the ball in injury-time but Connacht were unable to press home their advantage as Munster produced the crucial turnover.
Connacht: I Keatley, D Fanning, N Ta'auso, K Matthews (capt), F Carr, M Nikora, C Willis; R Sweeney, S Cronin, J Hagan, M Swift, M McCarthy, A Browne, J O'Connor, E Taylor.
Replacements: B Upton for McCarthy 80, M McComish for Taylor 41.
Not Used: A Flavin, B Fa'amausili, D Rogers, F Murphy, A Wynne, B Tuohy.
Munster: P Warwick, B Murphy, T Gleeson, L Mafi, D Hurley, R O'Gara (cpt), P Stringer; W du Preez, M Sherry, P Borlase, Donnacha Ryan, I Nagle, A Quinlan, N Ronan, P Butler.
Replacements: Dave Ryan for du Preez 72, J Hayes for Borlase 57, B Holland for Quinlan 48, T O'Donnell for Butler 57.
Not Used: S Henry, C Murray, J Murphy, S Deasy.
Referee: D Wilkinson (IRFU)