Northampton Saints are the only English side left in this season's Investec Champions Cup after a disappointing weekend for the other Premiership quartet in the last 16.
Eight English sides began their Champions Cup campaigns last December, but after Bath, Bristol Bears and Exeter Chiefs went out in the pool stages, Harlequins, Saracens, Leicester Tigers and Sale Sharks all exited the competition in the first knockout round.
Saints, seeking to become the Premiership's first Champions Cup winners since Exeter in 2020, are joined in the quarter-finals by four French teams, two from Ireland and Glasgow Warriors as Scotland's sole representation.
'Laws and injuries' to blame?
Saints' victory was as good as it got for the English sides, who collectively conceded 34 tries across their five matches.
Saracens rested England players Maro Itoje, Elliot Daly, Jamie George, Ben Earl and Tom Willis but raced into an early lead in France before being overpowered 72-42 by 10-try Toulon.
Harlequins picked their internationals, including England's Marcus Smith, but failed to land a shot as they were thrashed 62-0 by 10-try Leinster at Croke Park.
Leicester Tigers were comfortably beaten 43-19 at Glasgow in the final game on Saturday.
Saracens left out their Test stars, in compliance with England's player welfare guidelines, after prioritising their pursuit of a Premiership play-off place over a fourth Champions Cup title.
Director of rugby Mark McCall chose to select his England regulars for their Premiership matches against Harlequins and Leicester, forcing his hand in Toulon.
Tigers head coach Michael Cheika said "different teams are affected by different things", citing injuries for his side after captain Julian Montoya, Wales back row Tommy Reffell and England lock Ollie Chessum all missed the trip to Scotstoun.
"People are always looking for trends but in reality you have to take each individual game as it is," Cheika told BBC Radio Leicester.
"Saracens were affected by the laws of having to rest players. We had to rest one and have injuries off the back of the Six Nations, but it comes down to game day.
"There were a couple of things that weren't good enough and we weren't good enough to win."
It did not get much easier for Sale Sharks on Sunday as they travelled to defending champions Toulouse, who trailed at half-time before closing out a 38-15 win in the south of France.
What about the salary cap?
The Premiership salary cap has long been touted as a reason why English clubs may struggle in Europe.
The cap was increased from £5m to £6.4m at the start of this ...
