Half backs Conor Murray and Ian Keatley took down Saracens 14-3 in a tactical master-class at Thomond Park.
"We didn't try and rush it and play miracle plays," said Murray.
"We stayed patient and played in the right areas at the right times and got our reward."
Keatley could afford to go 2-from-six off the floor on a night when Munster bombarded their visitors with a hail of garryowens to move to the head of Pool1.
The ball spent more time in the air than on the ground for the opening forty as both sides took a safety first approach. Patience truly was a virtue.
It was all about forcing mistakes. Paul O'Connell nicked a lineout and Simon Zebo's threaded through ball put Alex Goode into a corner.
His clearance allowed a Munster maul which drew a penalty for Ian Keatley to make it 3-0 as late as the 27th minute. BJ Botha was spotted illegally binding at a scrum and pulling down a maul to hand over two penalties and precious territory.
Owen Farrell struck the equaliser when Tommy O'Donnell used his hands on the floor in the 37th minute before Keatley went one from three on the half-time whistle.
Saracens looked to lift the pace of the game. Chris Ashton began to come onto the ball. It took a mighty defensive scrum to snuff out the danger.
Then, replacement Rhys Gill saw yellow for hiking Peter O'Mahony's legs above the horizontal in the 51st minute.
The predictable surge came. Keatley shot Munster three clear.Andrew Conway cut a fine line. Keatley tickled the ball into the corner. Munster were in prime location.
The forwards went back to basics, driving it up for Conway to come up inches short of the line. There was a penalty as compensation and Dave Foley's lineout was powered over for Dave Kilcoyne's try for 11-3 on the hour.
A dream diagonal ball from Keatley deflected off Goode for an attacking lineout which the forwards trucked forward for Keatley to nail a drop goal.
It was all Saracens could do to stay in the game.
They could have suffered more damage were it not for the greasy night in Limerick.