The first Italian club to ever reach the PRO14’s knockout stages, Benetton were the better team and scored the game’s only try through Fijian winger Iliesa Ratuva on the stroke of half-time.
Tommaso Allan’s terrific touchline conversion gave them a 10-3 buffer, with Tyler Bleyendaal and Allan having exchanged earlier penalties.
Sloppy Munster were on the cusp of a shock quarter-final exit when Allan replied to Bleyendaal’s second penalty.
However, the latter’s replacement, Hanrahan, proved to be the hosts’ saviour as he knocked over a trio of penalties, including the decisive 76th-minute strike after Dewaldt Duvenage’s kicking away of the ball had moved the penalty into kicking range.
Munster’s collective relief was obvious as they advanced to their fourth PRO14 semi-final in five years – another all-Irish clash with old rivals Leinster at the RDS on Saturday, May 18.
Darren Sweetnam started in place of Keith Earls who failed a late fitness start, but the hosts were boosted by Conor Murray’s inclusion at scrum half.
Bidding to become the first Italian side to win at Thomond Park, Benetton absorbed the early pressure, Munster twice gaining ground with their maul but Toa Halafihi and Braam Steyn smothered Murray a few metres out.
Two more try-scoring chances went a-begging as Sweetnam was stopped short from a wide move, before Tadhg Beirne knocked on in a big defensive win for the Italians.
Bleyendaal opened the scoring with a long range 22nd-minute penalty after Murray was taken out at a ruck. However, no clear release saw Munster captain Peter O’Mahony quickly cough up three points to Allan.
High tackle counts from the Treviso forwards continued to frustrate Munster, whose attack was too predictable at times.
Marco Riccioni’s scrum penalty and Allan’s clever touchfinder clawed back hard-won territory late on, Hayward’s quickly-taken lineout and break paving the way for Benetton to go wide and Ratuva’s diving one-handed finish in the right corner stunned the mostly-red attendance of 10,042.
Following Bleyendaal’s second penalty just three minutes after the restart, Benetton showed their threat again with a slick Tito Tebaldi-inspired attack and, had Steyn held onto a pass, the try was on.
A similar knock-on from replacement Hame Faiva, in front of the Munster posts, ruined Ratuva’s excellent midfield break past four defenders.
Successive penalties, with CJ Stander and Hanrahan the guilty parties, led to Allan’s 59th-minute penalty, with Munster left to rue a lineout steal by Federico Ruzza.
Momentum was finally behind the hosts, though, as Hanrahan strung together two penalty goals for a 13-12 scoreline, rewarding the impact of the province’s bench.
It was Munster’s play-off experience which ultimately got them out of jail. Dogged defending saw Ratuva tackled short, the visitors then falling foul of referee Nigel Owens’ whistle as John Ryan and Stander won crucial penalties.
Kerry native Hanrahan stepped up to nervelessly nail his 50-metre kick and Munster desperately hung on despite the Italians’ strong carrying in the final minutes.
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