Sunderland seized the undisputed lead of the Championship after Chris Rigg and Romaine Mundle both scored to continue their superb start to the season.
The wingers struck either side of Elijah Adebayo's first Luton goal since May, with the win taking Regis Le Bris's Black Cats clear of Leeds, who had moved level yesterday.
It was a bitter blow for the Hatters, who had hoped a poor start to life back in the Championship was behind them following Saturday's demolition of local rivals Watford.
Sunderland started well, with Luton goalkeeper Thomas Kaminski needed after 60 seconds to deny Dan Neil, who was teed up by Alan Browne's trickery.
Browne was back again seconds later, with a backheel that Kaminski blocked after former Tottenham man Mundle had caused havoc down the other flank.
Rigg (centre) wriggled through to put Sunderland ahead in the 55th minute, keeping his feet in the box to slip a shot under Kaminski
Luton eventually got a foothold on the game and replied with a Carlton Morris effort on the turn, from Victor Moses's delivery, that fizzed the wrong side of the post.
Jobe Bellingham saw a drive deflected wide at the other end but a barrage of Hatters corners saw Black Cats keeper Anthony Patterson leap to keep out Mark McGuinness's header.
Another saw the ball bounce off the top of the Sunderland bar before 17-year-old Rigg was booked for hacking down Alfie Doughty, Luton's set-piece taker.
Morris thought he had fired Luton ahead on the brink of half-time, only to be denied by the offside flag.
Morris timed his run to the back post to perfection to meet Daiki Hashioka's flick-on but offside Jordan Clark was deemed too close to the action.
Rigg wriggled through to put Sunderland ahead in the 55th minute, keeping his feet in the box to slip a shot under Kaminski.
Tahith Chong was at fault for a poorly-placed backpass that the teenager intercepted.
The lead lasted just eight minutes as Adebayo celebrated his first goal of the season.
Morris volleyed Doughty's free-kick to the back post for his strike partner to nod in from close range.
But Sunderland snatched the winner two minutes later through Mundle's super finish.
Chong felt he had been fouled before Mundle capped off a swift counter as he found the bottom corner from the edge of the box to ensure that Le Bris's dream start to life in the North East continues.