Danny McGuire could not find the try he needed to set an outright Super League try-scoring record – and is now a doubt for the Challenge Cup final after limping to the dressing rooms in the 69th minute.
McGuire knows he will not have long to wait to set a new mark of 200 tries and overhaul the record he jointly holds with former Leeds team-mate Keith Senior.
Leeds decided against risking Jamie Peacock, Jamie Jones-Buchanan and Rob Burrow, who were all carrying minor injuries, but it took the home side just six minutes to break through as Ryan Bailey bulldozed his way over to leave Kevin Sinfield an easy conversion.
McGuire then combined neatly with Carl Ablett to send winger Ryan Hall diving over in the corner.
McGuire’s 200th Super League try almost arrived three minutes later when he received the ball well inside his own half and was caught inches short of the line.
However, Shaun Lunt was up in support and he grabbed the Rhinos’ third try.
Widnes had a spell of pressure but Leeds defended stubbornly until strong-running centre Stefan Marsh shrugged off three tacklers on his way to the posts, Patrick Ah Van tagging on the goal.
The Rhinos were soon back on the rampage. Zak Hardaker and Richard Moore scored tries, both improved by Sinfield, before Hall ran on to McGuire’s clever kick to the corner for his second try.
Widnes refused to drop their heads and captain Rhys Hanbury made an excellent break before putting Frank Winterstein in for their second try, Ah Van again succeeding with the kick.
Brett Delaney added the Rhinos’ seventh try just before half-time, Sinfield’s touchline goal stretching the score to 40-6.
There was concern as Hall and Widnes winger Willie Isa collided and needed treatment, but both recovered sufficiently to continue.
Widnes stuck to their task despite the heavy scoreline, tries in rapid succession by Cameron Phelps and Marsh restoring some pride, with Ah Van converting both.
But Leeds were in no mood to let things slip and Darrell Griffin, Kylie Leuluai, Steve Ward and Hardaker all scored further tries before substitute Jimmy Keinhorst crossed for the first Super League try of his career in the final minute.
Sinfield enjoyed a very successful night overall, being successful with 10 of his 12 conversion attempts.
Leeds Rhinos: Hardaker, Jones-Bishop, Watkins, Ablett, Hall, Sinfield, McGuire, Leuluai, Lunt, Griffin, Delaney, Ward, Bailey. Substitutes: Kirke, Clarkson, Moore, Keinhorst.
Widnes Vikings: Phelps, Isa, Marsh, Dean, Ah Van, Craven, Hanbury, Pickersgill, Haggerty, Davies, Winterstein, Allen, Cahill. Substitutes: J. Kite, Leuluai, Gore, Gerrard.
Referee: George Stokes (RFL).