Sunderland climbed into the top 10 of the Sky Bet Championship as they made a winning return after the World Cup shutdown.
Second-half goals from Amad Diallo, Alex Pritchard and Ellis Simms enabled the Black Cats to claim a 3-0 victory over Millwall, who succumbed tamely on Wearside.
Sunderland effectively settled things with a two-goal burst in the space of five minutes at the start of the second half, improving markedly after a slow start to claim what was only a second home win since August.
Millwall went into the game knowing a win would lift them into fourth position, and the visitors were the dominant force during a fractious opening half-hour.