Maclin suffered a hip pointer injury, which is considered to be somewhat serious and very painful. This occurred during Sunday's win over the Cleveland Browns.
Jackson was out with a pulled hamstring that flared up during Wednesday's practice. It is not expected to keep him from playing on Sunday against the Ravens.
Last weekend, Maclin and Jackson were Michael Vick's two most targeted receivers, combining for 11 receptions, 173 yards, and a touchdown.
If Maclin cannot play, rookie Damaris Johnson would be the likely replacement. Johnson was undrafted out of Tulsa, and caught one reception for ten yards in his first game last weekend.