Dynamo Moscow were the only favorite to win their game in the KHL playoffs, meaning the team could become the first outfit to reach the last 8 as soon as Sunday.
The Muscovites have one foot in the quarter-finals after beating their namesakes from Minsk 4-2 for the third time.
Other Western Conference leaders, SKA, Atlant and Torpedo Nizhny Novgorod, were less convincing on the day.
Denis Parshin netted the all-important overtime goal to give CSKA Moscow a 3-2 win at home to SKA St. Petersburg. The capital club pulled one back in their best-of-seven contest to trail, 2-1.
There was also a 2-1 overtime win for Severstal, who cut down the deficit in their series against Atlant.
And it was evenly poised between Dynamo Riga and Torpedo, 3-3, before Jānis Sprukts sent the home crowd rejoicing after a second overtime winner.