Aaron Rodgers' Brother -- Blasted By 'Bachelorette' Rival ... You're a 'Failed Football Player!'

HATERS BE HATIN'!!!!! Aaron Rodgers' younger bro, Jordan, made his debut as a suitor on "The Bachelorette" Monday night -- and while he was a HUUUUGE hit with rose-giver JoJo Fletcher ... the dudes were SUPER JELLY PANTS!!!