Leeds ran in seven tries as they demolished Cardiff Blues at Headingley.
HEINEKEN CUP POOL TWO
Leeds: (24) 48
Tries: Syman 2, Palmer, Biggs, Penalty try, Marshall, Doherty
Cons: Ross 5.
Cardiff Blues: (3) 3
Andre Snyman (2), Tom Palmer, Tom Biggs, Justin Marshall and David Doherty all crossed for Leeds, with the hosts also awarded a penalty try.
Gordon Ross landed five conversions and Marshall added a drop-goal, while the Blues managed a Nick MacLeod penalty.
The victory briefly put Leeds into the last Heineken Cup quarter-final qualifying spot, but they were later ousted by Leinster, who hammered Bath.
Leeds virtually guaranteed the victory with a superb first-half display, while the Blues were shambolic in comparison.
The Welsh side also needed a bonus-point win to keep their quarter-final hopes alive, but they never threatened the Leeds tryline.
Snyman's opening try on 14 minutes came from a Blues turnover which Marshall quickly exploited. Two passes later, the winger had a clear run down the right flank to score.
Leeds' second try on the half hour was all about forward power as the pack drove lock Palmer over from catch-and-drive lineout.
A third score soon followed as the home side went through several phases before centre Chris Bell found Biggs on his outside and the winger wriggled over for his first Heineken Cup try.
Gordon Ross added a superb conversion from the left touchline to maintain his perfect record.
The bonus point arrived five minutes after the interval, with former All Blacks scrum-half Marshall again the architect.
He shrugged off a weak tackle in midfield to open up the Blues defence, and fired a long pass out wide to Snyman who beat Blues scrum-half Mike Phillips on the outside.
The crucial fifth try arrived 10 minutes later. A superb counter attack took the home side near the Blues tryline, but Stuart Hooper failed to ground the ball over the line after a short drive.
The home fans were soon celebrating, though, when the referee awarded Leeds a penalty try after Blues collapsed the resulting five-metre scrum.
Ross made no mistake with the conversion from in front of the posts.
Another powerful scrum gave Marshall the opportunity to exploit a huge gap in the Blues defence for a well deserved unconverted try.
The Blues finally put some passes together in the final stages, but Leeds had the last say with another converted try after replacement Doherty won the race to Ross' kick ahead to dive over in the last minute.
Leeds director of rugby Phil Davies:
"I'm pleased we played as well as we did and we scored the tries we needed to.
"It makes it a bit more special to do it against such illustrious opposition as Cardiff. They are a side with tremendous history and tradition.
"And so it was one of the most meaningful results in the club's short history."
Cardiff coach Dai Young:
"To say I'm disappointed is a huge understatement. We were totally hammered in the contact area.
"We are a team that has to play with tempo and to get any tempo in your game, you need to get some go forward and produce quick ball.
"But Leeds dominated the tackle area. If they didn't turn the ball over - which they did numerous times - they at least slowed the ball down."
Leeds: De Marigny; Snyman, Vickerman, Bell, Biggs; Ross, Marshall; Shelley, Bulloch, Kerr, Hooper (capt), Palmer, Morgan, Parks, Thomas.
Replacements: Reid for Thomas (61), Gerber for Bulloch (61), Rawlinson for Shelley (61), Doherty for Snyman (65), Care for Marshall (66), Hyde for Parks (76).
Blues: R. Williams (capt); Czekaj, J Robinson, Stcherbina, Lomu; Macleod, Phillips; Jenkins, R Thomas, M Jones, D Jones, Sidoli, Powell, M Williams, Rush.
Replacements: Yapp for M Jones (51), Sowden-Taylor for D Jones (54), Quinnell for A. Powell (59), L Thomas for MacLeod (59), R Powell for Phillips (65), Goodfield for R. Thomas (73).
Not used: T Davies.
Referee: Christophe Berdos (France).