He has already been out for a couple of weeks. It is interesting to note that he started the season on the IL, and the Blazers struggled. He came back, and almost immediately they started winning. He started hurting again, and his shot went south, and the Blazers started to struggle. He went out, and the Blazers were a sub .500 team.
This is an example of how the dynamics of an individual player can impact a team in an outsize way. Jones, is a solid NBA player, but by no means a star, or even a potential star. He is a role player. When he was shooting well, he changed how defense had to play us. They couldn't double off his position, because if they did then Roy, Jack and Blake would find him in rhythm, and he would score with ease. This alone made Brandon Roy far more effective. Same thing can be said about Channing Frye. Roy plays much better with Frye instead of Przybilla, and Jones instead of Webster. Their ability to hit mid to long range jumpers, allowed Roy a greater ability to penetrate, and get to the rim. That ability also allowed him to get more FT, and also allowed him more space to shoot his jumper.
Roy has not been nearly as effective with Przybilla on the floor. This is the case even though Joel sets great picks. Roy often goes away from the pick, instead of trying to go at the big guy on a switch. Same with Webster. For Webster to be effective then you need to run plays for him, and run him off a couple of picks, and the catch and shoot. If the game is dribble drive kick out Webster is not nearly as effective. He is much more effective when Roy isn't on the floor than when he is.