VANCOUVER — Klim Kostin scored twice to lead Russia past Slovakia 8-3 on Wednesday in their quarterfinal matchup at the world junior hockey championship.

Russia (5-0-0-0) has not lost a game in the tournament and is now off to the semifinals, where they'll face the United States on Friday.

Grigori Denisenko put up a goal and a pair of assists in the victory. His teammates Alexander Alexeyev, Stepan Starkov, Nikita Shashkov, Kirill Slepets and Ilya Morozov also scored.

Martin Fehervary, Milos Roman and Michal Ivan responded for Slovakia (1-0-0-4), who outshot the Russians 35 to 30.

Pyotr Kochetkov made 32 saves for Russia. The undrafted netminder has allowed only three goals in the tournament so far.

The Slovaks switched out goalie Samuel Hlavaj in the first period after he allowed three goals on the first six shots of the game.

He was replaced by Juraj Sklenar, who stopped 19-of-24.

Denisenko opened the scoring 5:36 into the first and Russia dominated for the rest of the period, adding three more goals before the first intermission.

The Russians kept Slovakia off the board for two full periods before Fehervary scored a short-handed goal 3:35 into the third frame.

It was the first goal of the tournament for the Washington Capitals prospect.

Roman clawed out another for Slovakia with just 1:02 to go in the game and Ivan added one more with just nine seconds left.

The Slovaks only win at this year's world juniors was a 11-2 drubbing of Kazakhstan in the round-robin.

It's the second year in a row that Slovakia has been ousted from the competition in the quarterfinals. Eventual silver medallists Sweden beat them 3-2 last year.

Russia was also booted from contention in the quarterfinals last year when they were beat 4-2 by the U.S.

All four teams still in this year's tournament will get a rest day Thursday before the semifinals kick off in Vancouver on Friday.