The 1921Toronto Argonauts season was the 35th season for the team since the franchise's inception in 1873. The team finished in first place in the Interprovincial Rugby Football Union with a perfect 6–0 record and qualified for the playoffs for the second consecutive season. The Argonauts defeated the defending champion Toronto Varsity Blues in the Eastern Semi-Final before winning the Eastern Final over the Toronto Parkdale Canoe Club. The Argonauts faced the Edmonton Eskimos in the 9th Grey Cup game, which was the first time that a Western Canada Rugby Football Union team competed for the Cup. The Argonauts completed their first and only perfect season and won the franchise's second Grey Cup championship by a score of 23-0 in the first ever shut out in a Grey Cup game.
^2009 Canadian Football League Facts, Figures & Records, Canadian Football League Properties/Publications, Toronto, Ontario, ISBN978-0-9739425-4-5, p.294