Ismaila Sarr scored twice as Norwich's losing start to the Premier League season extended to five games after a 3-1 defeat to Watford at Carrow Road on Saturday.
The Hornets' record signing proved too good for the Norwich defense with his brace putting the game beyond the hosts.
The visitors had taken an early lead as Emmanuel Dennis headed past Tim Krul after being marked poorly in the 17th minute.
Teemu Pukki struck his, and Norwich's, second league goal of the season to level the contest when he beat the offside trap before sending the ball over Ben Foster 10 minutes before halftime.
Watford took a decisive lead in the 63rd with Sarr beating Grant Hanley to the ball before flicking it into the net.
Sarr was then first to a parried shot from Josh King to tap home for his second 10 minutes from time. The goal was originally ruled out for offside before a VAR review determined King had been onside when he received the ball from Tom Cleverley.
Norwich had the toughest of starts — against Liverpool, Manchester City, Leicester and Arsenal — but struggled against a fellow promoted side.
United States forward Josh Sargent made his first start in the Premier League for Norwich.
