Former NFL star Jamal Anderson took a beating on his Georgia mansion ... TMZ has learned his primo crib was sold off at a foreclosure auction ... for $225,000 LESS than what Jamal paid.
Jamal -- who played for the Atlanta Falcons from 1994 to 2001 -- bought the MASSIVE 10-bedroom, 9-bath crib way back in 1999 (when he had an NFL contract) for $1.225 million.
According to official records, Anderson defaulted on his mortgage ... so the bank foreclosed the home and recently sold it at auction for an even $1,000,000.
It was a STEAL for the buyer ... the pad is over 6,000 square feet, sits on 2 acres and is rockin' a separate guest house, arcade room, media room, pool and spa.
In other Jamal news ... TMZ has learned he just paid off that $1.1 million federal tax lien. Yay.