One source said the DOJ would rather risk losing a trial than drop its concerns about lost network competition in order to win a few slot and city pair divestitures. "It would be such a black eye to file a challenge on those grounds and then walk away," the source said. "I can't imagine them doing that."

How strong the DOJ's case will be in court is harder to predict, the antitrust lawyers said. Although the DOJ has a cohesive theory of how consumers will be harmed, whether U.S. District Judge Colleen Kollar-Kotelly buys it will depend on evidence contained in company documents and the impact of depositions -- all factors that won't be known until they are presented at trial.

-- Written by Lou Whiteman and Bill McConnell

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