NFL's Erik Walden -- Slashed with Knife ... Baby Mama Arrested

Indianapolis Colts linebacker Erik Walden was attacked by his baby mama ... who slashed him with a knife and attacked his female companion with a baseball bat ... this according to the police report.

The story is insane ... cops tracked down Erika Palmer, the mother of Walden's children, after she allegedly went on a rampage in Georgia on Saturday night.

Walden told police Palmer had been waiting at their home around 11:30 PM with a baseball bat and gun.

Walden says he was able to wrestle the gun away from Palmer -- but during the incident, she bashed Walden's female friend in the arm, severely injuring her right elbow. Walden says she also trashed the house and stole his $35,000 gold Rolex watch.

Palmer left the home ... but later returned ... and another struggle broke out. This time, she allegedly slashed Walden in the left upper arm with a knife ... causing a 4 to 6 inch gash.

Walden says Palmer ran from the home. Cops say they tracked Palmer's cell phone and found her in a nearby Hampton Inn ... where she was arrested on 16 charges including aggravated assault, battery, burglary, theft and criminal trespass.