After pool victories over Yorkshire Carnegie and Aberavon, he knows success against Ulster Ravens should see them secure their progress.
“It’s a massive test and we’re travelling over on the morning of the game, but that’ll be no excuse whatsoever,” he said.
“Our ambition is to win the pool and secure a home quarter-final spot.
“But if we don’t get the result we want in Ulster then we won’t be getting that home quarter-final; it’s as simple as that.”
Blackett includes three former Ulster players – James McKinney, Adam Macklin and Ali Birch.