Serbia's Aleksa Avramovic (L) goes for a layup during the FIBA Basketball World Cup quarter-final match between Lithuania and Serbia at Mall of Asia Arena in Manila on September 5, 2023. Photo: AFP
Bogdan Bogdanovic had 21 points for Serbia, who will play either Canada or Slovenia in the semi-finals on Friday.
Lithuania went into the game as the tournament's only unbeaten team after downing the United States in their previous outing.
But Serbia took control in the second quarter, outscoring Lithuania 25-13 to open up a lead that they never gave back.
Atlanta Hawks shooting guard Bogdanovic had 18 points in the first half alone for Serbia.
Bogdanovic finished as his team's top scorer, followed by Filip Petrusev with 17 points and Stefan Jovic with 11.
Tadas Sedekerskis was Lithuania's top scorer with 14 points, followed by Rokas Jokubaitis with 13.
Lithuania could not repeat the strong start they made against the US, where they nailed their first nine three-point attempts before going on to claim a 110-104 win.
Serbia were playing without power forward Borisa Simanic, who underwent surgery to remove a kidney on Sunday after being injured earlier in the tournament.
Simanic was hit by a South Sudan player's elbow during a pool game on August 30.
Nikola Jokic, who led the Denver Nuggets to last season's NBA title and was named MVP of the Finals, is not appearing for Serbia at the World Cup as he rests ahead of the new season.
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