Originally Muk got bumped up to the top pair when their 1D, Philip Larsen, got injured. The team was basically a lot of Larsen and then defense by committee when they started.
He was then paired with Larsen’s partner, Dinar Khafizullin, on the top pair when he first got more minutes in mid-September. Then Dinar got injured after three games w/ Muk and hasn’t played since 9/23.
They then reunited Muk with his original partner from the 3rd pair, Grigori Panin (the team’s 35 year old Captain), on the top line, while keeping their 2nd pair* intact.
Then, plot twist, Larsen, who had been out since 9/11, came back on 10/3 and Muk and Larsen are now paired on the top line. (Panin went back to the 3rd pair.) The nice part of him playing with Larsen is he’s a RHD, unlike Panin and Khafizullin.
Larson had brief stints in the NHL with the Stars, Oilers & Canucks and some might remember when Hall cranked his former teammate in 2016 (it was ruled a clean hit and he felt bad afterwards).
*(Mikhail Naumenkov & Pavel Koledov) if anyone is wondering.