Cork City retain the President's Cup
A Ronan Murray double had Dundalk comfortably ahead at the break in Oriel Park but goals from Karl Sheppard, Barry McNamee, Kieran Sadlier and Graham Cummins saw Cork claim the first piece of silverware of the 2018 season.
The Lilywhites had it all their own way during the first half and created the first chance of the game as Michael Duffy went close with a header from Dylan Connolly's right-sided cross with nine minutes gone.
Dundalk made their dominance tell in the 17th minute as new recruit Murray scored his first competitive goal for the club. Cork failed to clear a right-sided cross and Murray was on hand to slide the ball home past Peter Cherrie.
John Caulfield's men tried to hit back on the half-hour as the impressive Sadlier found space on the left to cross for Jimmy Keohane on the six-yard box but he only put the ball wide of the right-hand post.
Connolly saw his deflected wide go narrowly wide and Duffy hit the post from 25 yards before Murray grabbed his second of the game. Dundalk captain Dane Massey's cross wasn't cleared by Cork defender Alan Bennett and Murray lifted the ball over a helpless Peter Cherrie.
Caulfield brought on Sheppard and it only took the 26-year-old just three minutes to have the desired impact. Pre-season defensive rustiness was on display as Sheppard raced in, after goalkeeper Gary Rogers had a mix-up with his defenders, to find the bottom corner.
Last season's double winners sensed victory and soon after they were level. Sadlier found space on the left and his pinpoint cross found an unmarked McNamee, who directed his header in as the clock struck the 55th minute.
Stephen Kenny's side were left stunned and worse was to come as Cork took the lead with 12 minutes remaining. Sadlier, Cork's most impressive performer in the game, found space on the right to turn inside and find the bottom corner from 30 yards to complete the turnaround in some fashion.
Three minutes later, Cork guaranteed that they retained the President's Cup as Cummins netted from Sadlier's low cross to seal the win.
The regular season kicks off on Friday, February 16 and Cork will undoubtedly be favourites going into the opening night judging by this display.
Dundalk: Rogers; Poynton, Hoare (Benson 37), Shields, McGrath, Adorjan (Hoban 65), Massey, Folan, Duffy, Connolly (O'Keeffe 87), Murray.
Cork City: Cherrie; Bennett, Barry, Morrissey (McCarthy 88), Keohane (Sheppard 46), McCormack, Cummins (Adebayo-Rowling 88), Sadlier (McLoughlin 88), Griffin, Horgan (Beattie 46), McNamee.
Referee: Derek Tomney (Dublin).