White hadn't practiced this week due to a hamstring injury.
McCoy, meanwhile, has a hand injury and Martin has a knee injury.
Da'Quan Bowers and Akeem Spence were expected to share time in McCoy's place for the Buccaneers (0-2). Bobby Rainey started in place of Martin. Rainey had 22 carries for 144 yards last weekend against the St. Louis Rams.
Information from ESPN.com Buccaneers reporter Pat Yasinskas and ESPN.com Falcons reporter Vaughn McClure was used in this report.
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