Jones, a seven-time Pro Bowl selection, will miss his third straight game with a hamstring injury. Mack, a six-time Pro Bowl pick, will miss his first game of the season with a concussion.
A third starter, left guard James Carpenter, will miss the game with a groin injury.
Free safety Ricardo Allen is listed as questionable with a concussion. Allen was a full participant in practice on Thursday. Return specialist Brandon Powell (foot) and rookie defensive tackle Marlon Davidson (knee) are listed as questionable.
Russell Gage will start at the No. 2 receiver spot with Calvin Ridley again taking Jones' spot at No. 1. Matt Hennessy will replace Mack, and Justin McCray will start in Carpenter's spot.
The Falcons (4-10) had Friday off as they prepare to face the Chiefs (13-1).
Jones, the NFL's active leader in 100-yard games with 58, needs another 100-yard game to tie Marvin Harrison for third place on the career list behind Jerry Rice (76) and Randy Moss (64).
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