Two-time defending champions Leinster and four-time winners Toulouse crashed out of the European Cup on Sunday as Munster and Leicester sneaked into the quarter-finals.
Leinster, who have won three of the last four tournaments, became the first champions to exit in the pool stages since Wasps in 2008.
Leinster had their fate sealed when fellow Irish province Munster beat Racing-Metro 29-6 in Limerick in Pool 1 to deny them one of the two best runners-up spots available for the quarter-finals.
Munster ended their pool campaign second in the group behind Saracens and were level on points with Leinster, but edged their Irish rivals for a last-eight spot on tries scored.
“If we hadn’t reached the quarter-finals the people would be in the long grass, there would have been a lot of bullets being fired,” Munster coach Rob Penney said.
“If we hadn’t gotten the outcome, I would have still been proud of the progress we are making and the areas of growth we are getting,” he said.
At Welford Road, where 50 tonnes of snow had been removed from the pitch in the 48 hours leading up to the game, two-time champions Leicester topped Pool 2 with a gritty 9-5 win over Toulouse.
In a game played in treacherous conditions, the French side’s kickers — Lionel Beauxis and Luke McAlister — squandered 17 points with the boot as their team missed out on the knockout stages for the first time since 2007.
Toulouse scored the game’s only try early in the second half when winger Yoann Huget stumbled over the line, but Toby Flood’s three first-half penalties proved decisive for the Tigers.
“It was a game when it was almost easier to play without the ball,” said Richard Cockerill, Leicester’s rugby director.
In Limerick, Munster got the perfect start against Racing when French flanker Antoine Battut was sent off by referee Wayne Barnes in the fifth minute for kneeing Keith Earls in the head.
However, it took the hosts 20 minutes to go ahead as scrumhalf Conor Murray went over from 5m out — Ian Keatley, standing in for suspended flyhalf Ronan O’Gara, converted to make it 7-3.
The hosts added a second three minutes later as Ireland wing Simon Zebo rounded off a superb move, started by a devastating run by prop Dave Kilcoyne. Keatley, however, missed the conversion to leave the score at 12-3.
Munster ran in a third try through Mike Sherry before Zebo guaranteed the crucial bonus point.
After good work by Felix Jones, the 22-year-old tapped the ball through and outpaced the Racing covering defense.
Zebo then sealed his hat-trick when Earls fed the ball to him.
The pool’s other match saw English side Saracens top the table as they thrashed Edinburgh 40-7 with England wing Chris Ashton running in two tries and his international teammate Owen Farrell kicking 15 points.
The result left Edinburgh with the sorry record of six defeats and no points having failed to garner even a bonus point just a season after they reached the semi-finals.
In the quarter-finals, top seeded English champions Harlequins will welcome Munster, Clermont host last-eight first-timers Montpellier, Leicester go to Toulon while Saracens will welcome Ulster.