It probably will cost them whatever chance they have, along with injuries. But it'll probably only cost them against the Lakers. They can beat the Grizzlies without it, especially if they continue with this big rotation (highly unlikely) or if Randolph can't get at least close to the level he was at last season.
People seem to forget, but Randolph isn't 7-1 or 7-2, he's a mere 6-9. Sure, he's extremely strong, but physically, they can do a reasonable enough job on him. And Gasol, for all his size, is just not a dominant rebounder. The two of them played above their heads in the playoffs last season and fooled people into thinking they're better than they are. I'm not saying they're not either the second or third best big duo in the league, because they definitely are. They just don't compare to the Lakers duo.