Newcastle United's Checkatrade Trophy run was brought to an end after a gutsy first-half performance at the Stadium of Light.
A strong Sunderland side beat the club's Under-21s 4-0 thanks to an own goal and strikes from Charlie Wyke, Chris Maguire and Benjamin Kimpioka.
Newcastle, backed by 2,780 fans, had held out for 45 spirited minutes against the League One club.
But their resistance was broken after the break by two quick-fire goals on a bitterly cold night on Wearside.
The two sets of fans taunted each other throughout the 90 minutes.
Newcastle's support chanted "we'll meet again", while the home end sang "there's only one Mike Ashley" after seeing their team score a fourth goal.
United coach Ben Dawson had been without influential midfielder Sean Longstaff, who could be needed against Chelsea at Stamford Bridge on Saturday with Jonjo Shelvey and Mohamed Diame struggling with injuries and Ki Sung-yueng away for the Asian Cup.
Longstaff's younger brother Matty started, while Elias Sorensen – who yesterday signed a new long-term contract at St James's Park – led the line.
Sorensen's run of goals in the competition was to end at the Stadium of Light.
Jack Ross, meanwhile, only made six changes to the home side.
Sunderland started well. They pressed high up the pitch and tried to unsettle Newcastle in the first 15 minutes. Nathan Harker did well to get to a goal-bound header from Charlie Wyke.
United fought back. The visitors steadily grew in confidence, and Callum Roberts got the better of Reece James before rolled the ball across the six-yard box. Adam Wilson, however, couldn't get on the end of the cross.
Sunderland's Bali Mumba was booked for taking a swipe at Roberts before the break.
Ross replaced Duncan Watmore with Kimpioka for the second half.
Newcastle's performance, impressive up to then, unravelled after the interval.
Sunderland got their breakthrough in the 47th minute. Seconds after Jerome Sinclair struck the post, Kelland Watts inadvertently turned a Maguire cross past a helpless Harker.
Ross's side were soon 2-0 up thanks to a header from an unmarked Wyke.
Sorensen – who hadn't come close to adding to his four Checkatrade Trophy goals – then made way for Yannick Toure.
Dawson also sent on Rosaire Longelo and Juan Cumbreras, but there was no way back for his team, and Maguire netted a third for Sunderland with a 20-yard shot in the 78th minute.
Kimpioka added a fourth goal in the dying minutes.
Dawson's young players, having matched Sunderland's first team for 45 minutes, were given a standing ovation by the club's travelling fans.
SUNDERLAND: Ruiter, O'Nien, Ozturk, Flanagan, James, Watmore (Kimpiolka, 46), McGeouch (Hackett, 83), Mumba, Maguire, Wyke (Molyneux, 77), Sinclair. Subs not used: Stryjek, Diamon, Taylor, Hunter.
NEWCASTLE UNITED: Harker, Walters, Gibson, M Longstaff, Bailey, Watts, Allan (Longelo, 68), Sangare, Roberts, Sorensen (Toure, 56), Wilson (Juanito, 75). Subs not used: McEntee, Langley.