TMZ Sports has obtained photos of the bloody scene at Marco Pappa's apartment -- after the MLS player was stabbed ... showing a bloody knife and a blood trail from the kitchen to the bathroom.
As we previously reported, cops say ex-Miss Washington Stormy Keffeler called 911 on Dec. 17th to report an accident at her boyfriend's Seattle apartment -- but when cops arrived both she and Marco told cops they had no idea what happened.
Marco was stabbed in the torso and needed surgery -- he denied Keffeler was his attacker.