The 39-year-old woman entered a Malibu, CA home where the couple was staying through an unlocked door, grabbed the child and was stopped by the Hall of Fame quarterback and his wife, Jennifer.
They took the baby as the woman fled the home, the report says.
LA County sheriff's deputies who were in the neighborhood on another matter were flagged down.
They found the woman a few blocks away, took her into custody and booked her on kidnapping and burglary charges, according to TMZ.
Montana, 64, won four Super Bowl titles with the San Francisco 49ers, who play the Giants on Sunday at MetLife Stadium. The two-time Most Valuable Player also played two years with the Kansas City Chiefs before retiring at the end of the 1994 season.
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