Sieve is the 25th Expert stage in Super Monkey Ball 2 and the 54th Expert stage in Super Monkey Ball Deluxe. It also appears as the 164th Ultimate stage with continues and the 204th without continues.
This stage features a very long path with objects moving along it. There is a circular path near the end of the side closer to the starting platform of the very long path featuring two moving objects. There is a short path in front of this path with a moving object, and the rest of the very long path features a moving object. The goal is located at the end of the path sideways.
To get to the goal, roll along the first path. Then, roll along the circular path either way until you come to a perpendicular path. Then, roll along the next path, which is narrower. Be careful of the moving objects as they will knock you of the stage; be especially careful of the final moving object as the path on which it is is narrower than the previous paths. Once you are at the end, roll into the goal as soon as the moving object leaves it.