The Gemara (Berachos 61b) tells us, that Rabbah claimed to be a Beinoni, to which Abaye responded that if he were to be a Beinoni, then everyone else would be less than that (G-d forbid) - but does that prove that Rabbah must be a Tzadik (as the Alter Rebbe indicates in the first chapter of Tanya), or is Abaye merely commenting on Rabba’s statement, and not disproving it (and if so, how does the Alter Rebbe know that Rabbah was mistaken)?
I cannot speak for Abaye and I don't know the commentators on that, but I can give you a sketch of a Breslev reading of that Gemara. No, just the opposite. Abaye by his statement does not prove that Rabbah is a Tzaddik. Rather Abaye is saying on the contrary he should see his lowliness before H"Y's greatness, find his good points within him nevertheless, thus transforming himself by judging himself to the scale of merit (L. Moharan #282), and rely on His grace and chesed.