Where’s Kovalev drinking between fights come from?

I always read that Kovalev is a drunk and he drank all the time throughout his career etc and how all the drinking started to catch up with him during the Ward fights. Where are people getting this info? Or is it just haters stereotyping russians? The first time I saw it mentioned was in Breadman's mailbag before the first Kovalev/Ward fight. Breadman was asked his opinion on who would win. He said it was a 50/50 fight, but if the rumours he'd been hearing for a while about Kovalev not living a healthy life in between camps were true, that could swing it in Ward's favour. Afterward's, Breadman confirmed that he'd been referring to Kovalev's heavy drinking habits when he said that. If David Jackson is telling the truth, Krusher's drinking escalated to the point where he was getting boozed up during camps too.

Addiction is a tough albeit common problem.

it came out the moment Ward win over Kov was announced on the cards. The releaser of the news wanted to wait till the moment the cards were read to spill it, for some bizarre reason.

Wasn't he charged for assault while drunk by that woman after following her home from a bar or something? (pending court case) Then more recently, thrown off a plane for allegedly harassing a woman while drunk

... in fact: https://www.youtube.com/embed/byExU2GlfZc SERGEY KOVALEV CONFESSES "I DRANK A COUPLE BEERS A DAY! 2 SMALL BOTTLES OF VODKA! I CLEANED UP!

From himself. From buddies of the people who surrounded him during his career (it's my guess based on some rumours i've read..). May be from his book (didn't read it)..

... Kovalev himself underlined that he was sober when he went to a monastery to seek guidance... :)

Russian working class guys love to drink man.. Hell, Russian in general throw down and order a bottle of vodka when ever I partied with them. I think he actually cleaned up his act later in his career but he was a binge drinker for sure. I don't think he was ever those daily drinker type alcoholics though

Build to Kov vs Ward II, there was a lot of ish talking. That was the first time I heard that.