Ben Jones-Bishop marked his first appearance of the season with a brilliant two-try display as unbeaten Leeds claimed a 38-4 victory which burst Widnes' bubble.
With Leeds coach Brian McDermott having three top-class wingers to choose from in the shape of Tom Briscoe, Ryan Hall and Jones-Bishop, the latter has been forced to bide his time on the touchline this season.
But he was called upon at Headingley Carnegie with Hall rested and, with a very strong wind at his back in the first half, dotted down twice as Widnes failed to get up field in the face of some testing conditions.
Leeds cut loose in the second period and reached an outcome which ended Widnes' 100 per cent start to the season but so unexpected was their early charge that this defeat is not something they should stew on.
Kallum Watkins, Ryan Bailey, Kevin Sinfield, Rob Burrow and Jamie-Jones Buchanan also crossed for the Rhinos, while Rhys Hanbury scored Widnes' only try.
St Helens maintained their 100 per cent start to the season as the leaders beat Catalan 40-22 on the back of an electric opening 30 minutes.
The home side were always in control after accruing 24 unanswered first-half points - with Tommy Makinson crossing twice - and although opposing winger Michael Oldfield would reply with a second-half brace himself, that big deficit early on proved Catalan's undoing as they failed to chalk up their first victory.
The victory means Saints have now won each of their first five fixtures but, as head coach Nathan Brown admitted in his programme notes, sterner tests await with Leeds visiting Langtree Park in two weeks' time.
A hat-trick of tries from centre Iain Thornley helped Wigan to their second win of the campaign but it was another below-par performance from the champions.
Hull KR led 16-8 midway through the first half but they eventually ran out of steam and a 34-20 defeat leaves them still waiting for their first win of the season.
Matthew Bowen, Liam Farrell and Ben Flower also scored tries for the hosts, who were pegged back by first-half scores from Hull KR quartet Jamie Langley, Ben Cockayne, Liam Salter and Kris Welham.
Warrington notched their third win in a row to inflict more pain on Salford, who were defeated 28-12.
Salford have now lost three on the bounce after opening victories over Wakefield and London, hardly the form that is called for as owner Marwan Koukash insists on a top-six finish.
The visiting Wolves raced to a 16-0 lead with tries from Chris Bridge, Micky Higham and Gene Ormsby.
Salford managed two tries from debutant Dom Manfredi, on loan from Wigan, and another from Greg Johnson, but Warrington were never in danger.
They added further scores in the second half from Joel Monaghan and Roy Asotasi but the damage was done before the break.