Macaulay Langstaff bagged only his second Millwall goal seven minutes from time to earn the Lions their first victory over Norwich at Carrow Road since 1968.
Substitute Langstaff had only been on the pitch for three minutes when he coolly slotted home from Alfie Doughty’s ball to register his second Lions goal in 37 appearances.
Millwall were worth their win because of the way they stepped up in the second half as Norwich wilted in Liam Manning’s first game in charge of his boyhood club.
Norwich bossed possession early on, but they struggled to make this count against Millwall’s well-organised side.
German Steven Benda was making his first appearance in six months and the Millwall goalkeeper, signed on loan from Fulham, comfortably saved Jacob Wright’s free-kick.
Millwall might have snatched the lead before half-time and Vladan Kovacevic denied Camiel Neghli.
The Lions kept up the pressure and Tristan Crama crossed from the right to the back post for Neghli to control with his first touch before scoring with his second to give the visitors a 52nd-minute lead.
Josh Sargant levelled two minutes later when he showed great desire to charge down Benda’s clearance and the ball rebounded off the Norwich striker and into the net, off the post.
Femi Azeez should have restored Millwall’s lead, but skied the ball over from close range when he had the goal at his mercy before Langstaff’s late intervention.