Munster hammered Ulster 64-7, while there were also wins for Edinburgh, the Ospreys, Leinster and Glasgow Warriors in the Pro14.
The Irish derby was the headline fixture of the round, but the match turned out to be an aberration. Munster ran in nine tries to Ulster’s one to register their biggest win yet over their arch-rivals.
Captain Peter O’Mahony and centre Dan Goggin scored two tries each, Joey Carbery contributed 15 points via a try and five conversions, and wing Keith Earls added a try and three conversions.
Munster secured the bonus point in the first half and held a 29-0 lead at the break.
Ulster struck first in the second half when Darren Cave dotted down. But any hopes of a comeback were ended as the hosts bagged five more tries to compound Ulster’s misery.
In other results, Edinburgh held off a late fightback by Treviso to record a 31-30 win, the Ospreys defeated hosts Zebre 22-8, Leinster inflicted a 20-3 defeat on Connacht, and the Glasgow Warriors returned to winning ways with a 29-13 victory against the Dragons.
Round 5 results:
Munster 64 Ulster 7
Edinburgh 31 Trevis 30
Ospreys 22 Zebre 8
Leinster 20 Connacht 3
Glasgow Warriors 29 Dragons 13
Cardiff Blues 24 Cheetahs 21
Scarlets 54 Kings 14