The Cincinnati Bengals remain winless as they continued their awful NFL season with a 24-10 defeat by the LA Rams in front of 83,720 at Wembley.
After two games at Tottenham Hotspur's new home, Wembley staged the first of its two matches this season with the Rams comfortable winners.
After Josh Reynolds scored the first touchdown of the evening, Joe Mixon ran in to briefly have the Bengals level.
But the dominant Cooper Kupp and Todd Gurley scored in the second half.
The Bengals now have an 0-8 record and are bottom of the AFC North division. Their worst ever NFL season came in 2002 when they won just twice.
The Miami Dolphins are the only other team yet to win in the NFL, and they play Pittsburgh in the early hours of Tuesday morning.
The Rams - beaten in the Super Bowl last season - have won five matches this season and remain in play-off contention in the NFC West.
The Houston Texans face the Jacksonville Jaguars at Wembley in the last game of this year's London series, which will be shown live on BBC Two next Sunday (3 November, from 14:00 GMT).