Grimsby Town were narrowly beaten by League One Sunderland in an entertaining Leasing.com Trophy group stage encounter at the Stadium of Light.
After a goalless first half, the Mariners took the lead though Matt Green on the hour but were pegged back eight minutes later when Duncan Watmore equalised.
Sunderland completed the turnaround when Marc McNulty put them ahead but Town fought back and Elliott Whitehouse made it 2-2.
But they were unable to hold on and force a penalty shootout as a Will Grigg header gave the hosts all three points and meant the Marines cannot now progress beyond the group phase of the competition.
As expected, Grimsby boss Michael Jolley named a much-changed line-up for the trip to the north-east, with only James McKeown, Harry Davis, Jordan Cook and Moses Ogbu remaining from the team that lost to Mansfield on Saturday.
McKeown started in goal, behind a defence of Elliott Hewitt, Davis, Mattie Pollock and Sebastian Ring.
Cook, Whitehouse and Charles Vernam were the midfielders, with Ahkeem Rose and Ogbu either side of Green in attack.
The substitutes were Sam Russell, Liam Gibson, Luke Waterfall, Jake Hessenthaler, Harry Cardwell, Joe Starbuck and Luis Adlard.
Sunderland came into the game hours after sacking manager Jack Ross, whose last match in charge proved to be Saturday's defeat at Lincoln.
Attackers Watmore and Grigg were likely to be among their main threats.
Town's first opportunity to get the ball into the danger zone came with a free kick on nine minutes but Cook's delivery was comfortably caught by home keeper Lee Burge.
A chance came at the other end soon afterwards when Luke O'Nien took advantage of a poor pass out of the Grimsby defence but his shot from 20 yards went over the bar.
Hewitt then did well to deny Marc McNulty inside the box after a long ball from Burge as the hosts continued to attack.
Watmore's run on 17 minutes brought another chance for Sunderland but after he found McNulty, the striker's shot was blocked for a corner.
McKeown was then called into action to tip an effort from Grant Leadbitter over the bar for another corner, which was cleared.
Green had a chance at the other end after a cross from Ring on the left fell for him but after turning, the striker's low shot was stopped by Burge.
Another cross, this time from Whitehouse, saw Green penalised for a foul on the keeper, who required treatment after appearing to have a hand injury but was passed fit to continue.
A drive from Watmore on 34 minutes was pushed away by McKeown, before a header from McNulty was comfortably stopped after the home side kept possession.
Sunderland won a corner on 38 minutes and the delivery from the flag was touched away by McKeown for another one, although the hosts were unable to cause significant problems from it.
A cross from Vernam on the Town left brought an opportunity for Green on 42 minutes but his weak header was comfortable for Burge.
Green then broke down the right and pulled the ball back for Rose, whose attempted shot was blocked.
One added minute was played at the end of the half and with no further chances for either side, the game remained goalless at the break.
No changes were made before the restart and an early chance for Watmore led to McKeown making a good save with his feet.
Watmore then curled a shot wide as Sunderland's strong start to the second half continued, before a spell of Town possession ended with a foul by Whitehouse near the corner flag on the right.
Hessenthaler replaced Rose in the game's first substitution on 55 minutes, before McNulty tried a first-time shot from 20 yards but could not keep the ball down.
The deadlock was broken just before the hour and it was the Mariners who took the lead. Ogbu played the ball back for Hessenthaler and his cross was met at the far post by GREEN, who sent a cushioned volley past Burge.
Sunderland's response saw Denver Hume get down the left and send over a low cross for Watmore, who turned and fired over the bar.
Cardwell replaced Vernam before a foul on O'Nien gave the home side a free kick on the right on 64 minutes but the delivery from it was cleared.
The hosts did manage to get themselves level four minutes later though. Ogbu lost possession and George Dobson's shot from 20 yards was saved by McKeown but WATMORE was first to the rebound to convert from close range.
Dobson was shown the yellow card for a foul on Green, before Cook sent a shot wide of the far post from the left after good build-up play by Town.
A free kick from Leadbitter on 77 minutes bounced through to McKeown but the turnaround was complete a minute later when Sunderland took the lead. The ball was cut back from the right for McNULTY, whose shot went into the net from close range.
But the hosts were not ahead for long, as the Mariners fought back to level the scores on 81 minutes. A low cross from Pollock on the left fell into the path of WHITEHOUSE, who just beat Ogbu to the ball and steered it past Burge.
Waterfall replaced Ring with seven minutes to go but two minutes later, the home side had their lead back again when a cross from Hume on the left was headed home at the far post by GRIGG.
Watmore was replaced by Lee Connelly for the last two minutes, plus the four added minutes which were signalled by the fourth official.
Grigg made way for Cole Kiernan as the Mariners pressed for a late equaliser but it was not to come and Sunderland took the points.
It means the Mariners remain without a point from their two games so far, with Leicester City U21 to come in their third and final group fixture later this month.
Before then, attention turns back to the league programme, starting with Saturday's trip to Stevenage.
Sunderland: Lee Burge, Bali Mumba, Denver Hume, Brandon Taylor, Joel Lynch, George Dobson, Duncan Watmore, Grant Leadbitter (C), Luke O'Nien, William Grigg, Marc McNulty.
Subs: Anthony Patterson, Jack Bainbridge, Laurens De Bock, Daniel Neill, Lee Connelly, Lynden Gooch, Cole Kiernan.
Town: James McKeown (C), Elliott Hewitt, Sebastian Ring, Matthew Pollock, Harry Davis, Jordan Cook, Charles Vernam, Elliott Whitehouse, Ahkeem Rose, Moses Ogbu, Matt Green.
Subs: Sam Russell, Liam Gibson, Luke Waterfall, Jake Hessenthaler, Joseph Starbuck, Luis Adlard, Harry Cardwell.
Referee: Stephen Martin
Possession: Sunderland 63% - 37% Town
Corners: Sunderland 4 - 0 Town
Next Up: Stevenage (A)