Manziel shot to prominence last season when he became the first freshman to win the Heisman trophy, but the headlines surrounding him turned negative during the off-season.
The 20-year-old was banned for the first half of his side's opening match of the season after an NCAA investigation into allegations that he had been paid to sign autographs. When he did come on, he was handed a 15-yard penalty for taunting and was promptly benched by his coach.
However, Flacco admits that he is a fan of the man dubbed 'Johnny Football' and believes that the more people dislike him, the bigger a fan he becomes.
"I don't know if I'll be too popular for this, but I don't know how I really felt about Johnny Manziel, but I feel like now everyone hates him. He's quickly becoming my favourite player in college football," Flacco told the Carroll County Times in Maryland.
Flacco, who named named MVP in his side's winning Super Bowl performance last season, will take part in the opening match of the new campaign as the Ravens travel to face the Denver Broncos on Thursday.