A much-changed Tigers side had looked on course for a fourth-round place after Jon Toral’s goal early in the second half, but Millwall substitute Shane Ferguson turned the tie with two goals in the final ten minutes.
Nigel Adkins made eight changes to his side with only Eric Lichaj, Kevin Stewart and Chris Martin remaining from the eleven that started against Bolton Wanderers on New Year’s Day. Lichaj wore the captain’s armband.
David Milinkovic made his first start of the season while George Long and Nouha Dicko were amongst the others to come into a 4-4-2 formation. The bench included a number of Academy products including Lewis Ritson and Keane Lewis-Potter.
Millwall made the brighter start without creating any real openings and there was little action of note at the other end of the field in a quiet opening quarter.
The first half-chance came the Tigers’ way when Stewart met a Toral corner with a flicked header at the near post but the attempt went wide.
A good cross from Milinkovic created an opportunity for Toral at the far post but he opted to knock the ball back into the middle rather than look to hit the target himself before Millwall had their first chance when Tom Elliott knocked the ball down for Aiden O’Brien to drag a shot across the face of goal.
Both goalkeepers were then called upon for the first time just before the half-hour. First Long made a fantastic save to keep out O’Brien’s close-range header before the play quickly switched to the other end where Todd Kane was denied by Jordan Archer.
Long was on the spot again to deny Elliott with O’Brien then having another chance that this time he flicked just wide as the half ended goalless.
Toral had the first attempt of the second half as he sent a volley well over the bar and it was Toral who opened the scoring in the 52nd minute. He was the architect as he played Dicko in down the right and when a low ball was played in to the near post, Toral had continued his run to apply a neat finish.
Dicko had the chance to add a second soon after when he found himself on the end of Lichaj’s cross but he couldn’t keep his header down before Long once again foiled O’Brien with a save at the other end.
Millwall made a triple change just after the hour as they looked to turn the tie before the Tigers’ first change came with 15 minutes remaining as Max Sheaf replaced Toral.
Long made routine saves from Jed Wallace and Shaun Williams, with O’Brien’s lack of luck continuing as his effort struck the underside of the bar.
A second change from the Tigers brought a debut for Lewis-Potter but Millwall were soon level as Ferguson gave Long no chance with a curling effort from 20 yards.
Ferguson completed the turnaround five minutes from time with a free kick from 20 yards, curled over the wall and into the net.
Millwall: Jordan Archer, Jake Cooper, Jed Wallace, Mahlon Romeo, Alex Pearce, Ryan Tunnicliffe (Steve Morison 63), Tom Elliott, Aiden O’Brien, Murray Wallace (Shaun Williams 63), Jiri Skalak (Shane Ferguson 63), Ryan Leonard.
Subs Not Used: David Martin, Lewis White, James Meredith, James Brown.
Hull City: George Long, Todd Kane, Robbie McKenzie, Ondrej Mazuch, Eric Lichaj, Jon Toral (Max Sheaf 75), Daniel Batty, Kevin Stewart, David Milinkovic, Chris Martin, Nouha Dicko (Keane Lewis-Potter 81).
Subs Not Used: David Marshall, Reece Burke, Evandro, Brandon Fleming, Lewis Ritson.
Referee: Mr A. Woomer.