Poland were no match for Russia, falling 79-57 despite 18 points from Magdalena Leciejewska.
The Russians stormed out to a 25-12 first-quarter lead to take a vice-like grip on the contest and never turned back.
Victory has put Russia through to the next phase from Group C while the Poles are eliminated from medal contention after two defeats.
Bulgaria Overcome Finns
Finland came from behind to beat Greece in their Group A opener but they were on the receiving end in their second match as they slumped to defeat against Bulgaria.
The Bulgarians, for whom Jaklin Zlatanova had 20 points, trailed 35-31 at half-time but outscored Finland 25-8 in the third quarter en route to a 65-53 win.
Finland must prevail in their encounter against the winless Czech Republic on Sunday to advance.