The invention relates to an article of footwear having an upper and a sole structure secured to the upper, the upper comprising a knitted element formed from at least one mechanically manipulated yarn, the knitted element having an area with a first layer and a second layer at least partially coextensive with the first layer, the first layer being formed of unitary construction with the second layer, and the second layer being joined to the first layer at opposite sides of the second layer. The knitted element is obtained by flat knitting and the knitted element comprises a pocket obtained through the flat knitting process as a unitary construction with the knitted element and the pocket is configured to have an upper opening and to be otherwise closed.