Dennis Schroder's Wednesday night went from awesome to pretty crappy real quick ... 'cause just after the Lakers point guard helped his team beat the Spurs -- a vehicle he was riding in was stopped by cops in Hollywood.
Cops tell TMZ Sports ... it all went down at around midnight, just a couple hours after the Lakers game had ended. According to an LAPD spokesperson, the stop was initiated after the vehicle allegedly had improper plates.
Video from the scene shows cops spoke with Schroder and what appeared to be his driver for about half an hour after pulling over the ride at a gas station.
It all seemed cordial, according to videos of the interaction ... with Schroder, at times, sporting a big smile on his face.
"I don't know what happened," the 29-year-old told a camera person during the stop. "I'm still surprised."
The LAPD says someone received a citation for improper plates during the stop, though it's unclear who the alleged violator was. Video shows Schroder was allowed to leave the scene without any issue.
Schroder's night had been going very well up until the pullover -- he played 37 minutes in the Lakers' win over San Antonio at Crypto.com Arena, logging nine points, eight rebounds, five assists, four steals and two blocks.
The victory was an extra sweet one for Schroder and purple and gold -- as it marked the first time the team had LeBron James, Anthony Davis and new addition Rui Hachimura on the floor at the same time this year.