In Raahe, a small port town more than 400 miles north of Helsinki, Donskoi and Salomaki played on the same youth hockey team, called Teräskiekko, from the time they were 5. They also played in the same midfield on many of the city's youth soccer teams.
"We're kind of different players, so it is not easy to compare," Salomaki said. "I don't know. He is a skilled player and good with the puck and I'm more like in a defensive role. It's hard to say who's better."
But when it comes to who is better on the soccer pitch, Donskoi said there's no debate.
"Miikka was the better soccer player," Donskoi said, flashing a rare smile. "He had a gift for it. I did not have those gifts, and I just stuck to the hockey side of it."
Despite the rivalry inherent in their friendship, their families remain best of friends and are on speaking terms back home, even if Donskoi and Salomaki have ceased communication during the series.
They also know it is more than just their families in Raahe who are interested in this series.
"Everyone back home is watching," Donskoi said, although the games start early in the morning in Finland because of the time differential; Raahe is eight hours ahead of Nashville and 10 hours ahead of San Jose.
Donskoi, 24, left Raahe first, moving to Finnish hockey club Karpat in 2009, when he was 15. Salomaki, 23, followed two years later.