Ulster's Guinness Pro14 play-off hopes were dashed as they blew a 10-point half-time lead and a last-minute scoring opportunity in a 24-24 draw against Munster at Thomond Park.

The northern province required a bonus-point win to potentially pip Edinburgh to third place in Conference B, but Munster lock Gerbrandt Grobler stole an 80th-minute lineout, five metres out from his own line, to knock the visitors out of title contention.

Duncan Williams and Stuart McCloskey swapped early tries in this lively inter-provincial tie, Brian Scott following up with a second Munster score before Rory Best touched down twice from mauls while Robin Copeland was in the sin-bin.

The Ireland captain's brace opened up a 24-14 interval lead for Ulster, yet Munster, who were already assured of a home semi-final qualifier next Saturday, held the edge in the second period with Copeland touching down and JJ Hanrahan landing a levelling 68th-minute penalty.

Only Sam Arnold remained in the Munster XV from last Sunday's Champions Cup semi-final defeat, and the freshened-up home side swiftly hit the front. Copeland dislodged the ball from David Shanahan's grasp after just a minute and returning scrum-half Williams dribbled through to score.

Hanrahan converted following TMO confirmation, but Ulster were level by the five-minute mark, Clive Ross gobbling up a loose pass and, although Darren Sweetnam successfully chased down Jacob Stockdale, the scoring pass was supplied to supporting centre McCloskey.

Johnny McPhillips converted and tagged on a penalty on the quarter-hour, rewarding the visitors' scrum, but Ulster, who were already missing John Cooney and Charles Piutau, lost both Iain Henderson and McCloskey to injury, the latter's head knock bringing Ireland Under-20 centre Angus Curtis on for his second appearance.

Munster struck for their second converted try via Sweetnam's superb surge when running back a kick. Captain Mike Sherry and James Cronin, the province's latest centurions, attacked closer in before tighthead Scott drove over for Hanrahan to convert.

However, referee Ben Whitehouse's harsh sin-binning of Copeland for a maul collapse gave Ulster the chance to retake the lead. The resulting lineout drive saw Best pile over in the 32nd minute and he did likewise just before the break, with timely support from Alan O'Connor.

Munster replied in the 48th minute, Ulster centre Luke Marshall seeing yellow for no clear release near his own line, and Copeland dived over from a subsequent ruck, with Hanrahan adding the extras for 24-21.

The remainder of the game was scrappy with a niggly undercurrent. There were handbags after Rhys Marshall and Best had tangled, but Ulster were now struggling to get out of their half.

Their set-piece really crumbled, the long arms of Grobler gobbling up a series of Ulster lineouts and replacement prop Stephen Archer winning some momentum-building scrum decisions. Dave O'Callaghan's timing at the breakdown allowed Hanrahan to kick Munster level.

A miscued drop goal from Hanrahan was the closest Munster, who will host Edinburgh in a week's time, went to going back in front. Nonetheless, the home side's defence denied Ulster any further try-scoring chances, with Jono Gibbes' charges now set for a Champions Cup qualification play-off at home to the Ospreys on May 18/19.