I can be here subjective, so you can skip if argument won't be good.
Lithuania beat Latvia, made great decisions in defense to stop Zagars and Porzingis duo. Even Porzingis made a lot of points, he worked for them very hard, made 10/15 FT. Only Lomasz and Porzingis made double digit points. Other players was stopped, Bertanis scored only 3 points. Lithuania had plan and even without main PG they were better whole match.
Greece won against Israel, Giannis scored 37 points, he shot only 2 FT in whole match, so Israel was very soft, i don't think there will be such an easy match against Lithuania for Giannis. Like i said before, Greece struggling, especially without Giannis.
This is 1/4 finals and underdog status very good for Lithuania, no pressure.
I would give small advantage to Greece, just because Giannis is monster, but Lithuania can live with his 30 pts, just other players need to be stopped. For me clear value bet.