Great experience had by Academy youngsters
It took Millwall five minutes to reclaim the lead with Mason Saunders-Henry blasting the ball into the roof of the net from the edge of the penalty area.
The Lions had chances to extended their lead, but it was the opposition who once again levelled the scores with Thierry Baba heading the equaliser from Ronan Manning's cross.
It was a promising start to the tournament for Millwall, but a bruising encounter saw Academy boy Kris Queeley injured and sidelined for the next game against Northern Ireland, and subsequently the rest of the competition,
This time it would be the Londoners who headed for the changing rooms facing a one-goal deficit at half-time.
A superb save by the Northern Ireland keeper, shortly after the re-start kept the scores level, but sustained pressure by Millwall eventually paid dividends 14 minutes into the half when a deflected shot fell invitingly for George Alexander, who made no mistake in burying the ball.
The Lions looked to be heading for a hard-earned point until Northern Ireland frontman Mark McKenna dribbled past his marker a placed his shot superbly in the corner of the net, with only five minutes to spare. It was only the Millwall goalpost that stopped McKenna from stretching their lead further just a few minutes later as Northern Ireland went home with the spoils.
This defeat left the young Lions facing the Republic of Ireland in a must-win third game if they were to retain the Mayo Cup.
Connelly was instrumental in the ROI's second goal just six minutes later. His low shot was parried by the Millwall keeper, straight into the path of Thomas Caffrey who slotted home to make it 2-0.
The second-half saw little difference in the timbre of the game with Connelly continuing to torment the Millwall defence. Ten minutes into the half ROI extended their lead with arguably, the goal of the tournament. A clearance from the Millwall penalty area fell to Jordan Doherty, whose 25-yard thunderbolt left the Millwall keeper clutching at thin air.
Shortly after this, ROI laid the icing on their cake with goal number four to extinguish any lingering hopes for the visitors. Once again it was the ubiquitous Connelly handing out the punishment with a fine header to double his goal tally and seal a comfortable 4-0 win.
Chesterfield 1-2 Millwall
Millwall continued to monopolise possession in the second-half and just rewards were earned when Mason Saunders-Henry was fouled on the edge of the Chesterfield area, and Ruben Duncan stepped forward to drill the resulting free-kick into the back of the net.
Chesterfield pulled one back late in the game from a corner, despite the protests from The Lions who claimed a foul on their keeper. But it was Millwall who earned the laurels in their final game with a 2-1 win.
Millwall's travelling party was as follows: Mick McDuff, Joe Wright, Prince Amoah, Dan Choules, Kris Queeley, Toby Stevenson, Rob Strachan, Ruben Duncan, Nathan Carlyle, Lewis West, Anthony Gale, Mason Saunders-Henry, Harry Taylor, Jethro Hanson, George Alexander, Abolaji Williams and Mel Jeffries.
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