Manziel's first CFL game, as the starting quarterback for the Montreal Alouettes against the visiting Hamilton Tiger-Cats last Friday, attracted an average audience of 406,000 on ESPN2 - making it the most-watched game for ESPN since it started showing CFL contests in 1980.
The previous record was a Saskatchewan-Edmonton game in June 2013 that drew an average of 347,000 viewers on ESPN2.
The Manziel game drew a combined average audience of 730,000 on TSN and RDS. It did not represent a season high in Canada as several games have had more than 900,000 viewers this year.
Manziel, a former Heisman Trophy winner, threw four interceptions as the last-place Alouettes lost 50-11 to Hamilton.