The Canadian club withdrew from their inaugural season in the top flight in July, citing financial problems caused by the coronavirus pandemic, but expressed the hope that they would return next year under new ownership.
However, a meeting of the Super League board on Monday rejected their submission by a vote of 8-4 with one abstention.
Leeds were one of three clubs to support the Wolfpack case, along with the Rugby Football League, whose single vote was cancelled out by that of Super League’s executive chairman Robert Elstone.
Toronto businessman Carlo LiVolsi, the club’s prospective new owner who had made a pledge to pay five months of unpaid wages to the players, made an online presentation to the club representatives.
Super League must now decide whether to run with 11 clubs in 2021 or find a 12th member.
Toronto were formed in 2016 by Canadian entrepreneur Eric Perez and, after starting out in League 1, won promotion twice in three years to claim their place in Super League.
They played in front of crowds of 9,000 in their Championship season but hopes of capitalising on the signing of Sonny Bill Williams for 2020 were scuppered by an inability to play any games in Toronto.
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