I don't believe it was ever expressed outwardly, but I seem to recollect from somewhere that Alexei Kovalev and Jaromir Jagr's relationship in Pittsburgh was icy at best.
What did he do to J.S.?
Barrasso seemed like one of the biggest jerks in the league. After the Sens were knocked out by Toronto in 2000, ol Brass Ass failed to show up for the final team meeting.
There are conflicting reports on specifics, but when Aubin was an up and coming goaltender and found himself as Barrasso's backup, Barrasso would berate the younger netminder mercilessly after sub-par performances, or at least what Barrasso perceived as sub-par performances. Things got worse the next season when Aubin became the Penguins starter, and Barrasso would alternate between outright belittlement, or at times going long stretches where he'd simply ignore Aubin's presence altogether. Basically, he bullied him.
The word is it once resulted in Barrasso throwing a chair at Aubin. He was traded to Ottawa before too long.
I don't know why he acted that way. He had a reputation sure, but he mostly just despised the media and saved his jerkness for them, former teammates always seemed to get along with him just fine. His daughter was sick with cancer sometime in the late 90s, I don't know if the timelines match up but that could have had something to do with it, combined with his place as an indispensable piece of the Penguins make up slipping fast.
I don't think anyone really knows how bad it got, whether it was persistent bullying or just the occasional flare-up. Neither Barrasso, Aubin or anyone from those teams has ever said anything about it as far as I know. I do feel bad for Aubin though, he was a promising young 'tender at the time, I wonder if there were lingering negative effects from his days with Barrasso that assisted in his fizzing out a few short years later.