10-man Swansea inflicted a first home defeat of the season on Millwall on Saturday evening as the visitors came from behind to win 2-1.
Courtney Baker-Richardson was shown a straight red card for a reckless lunge on James Meredith just four minutes in and after Murray Wallace nodded home just after the hour-mark, it looked as though The Lions were on their way to victory.
However, a turnaround from The Swans saw Kyle Naughton and Oli McBurnie net to win the game for the away side.
Neil Harris handed Ben Amos a first League start in goal for The Lions, whilst Ryan Tunnicliffe and Murray Wallace retained their places in the starting XI from last Sunday's defeat at Rotherham United.
Just four minutes in The Swans found themselves a man light as Baker-Richardson was shown a straight red card for a tackle on Meredith.
The Aussie required medical attention for a few minutes but rose to his feet - a free-kick from Shaun Williams followed, but the midfielder's low grubber rolled into the arms of Ewrin Mulder.
On 13 minutes Gregory sprung the offside trap and broke forward but his vicious cross was too high and wide for Meredith.
Ten minutes later The Lions really should've taken the lead, but Jed Wallace skewed his shot wide after being put clean through by Steve Morison's knockdown.
With 27 minutes on the clock The Swans broke away following a Millwall corner, but outstanding defensive work from Mahlon Romeo kept the score goalless as Daniel James looked to pull the trigger inside the penalty area.
Just after the half-hour mark The Lions almost scored an extraordinary goal through Lee Gregory, but after the striker flicked Morison's header towards goal, it crept wide.
Millwall spent the remainder of the first-half near enough camped inside the Swansea half, but were unable to find the opening goal.
Five minutes into the second-half Swansea launched an attack and were inches from opening the scoring as Mike van der Hoorn was just unable to get on the end of a cross inside the six-yard box.
On 56 minutes Aiden O'Brien battled his way to the edge of the penalty area but blazed well wide, whilst at the other end James had an effort blocked. Jed Wallace, meanwhile, shot over as the first goal still eluded the game.
With 62 minutes on the clock, it came. Williams' corner was deep and headed back into danger by Jake Cooper where Murray Wallace was waiting to nod home his first Lions goal.
Just 20 minutes remained when substitute Jiri Skalak broke free down the right-hand side, but the winger's cross was agonisingly missed by Tunnicliffe at the back post.
In the 76th minute, Swansea were level. Two substitutes in Jefferson Montero and Naughton combined, with the former laying the ball off to the ex-Spurs man, who drilled home low past Amos - who up until that point had had nothing to do.
The Lions could have had taken the lead straight after the resumption of play but Gregory pulled his shot wide of the post from another Morison lay-off.
On 82 minutes Millwall fashioned another chance, this time through Skalak, but the Czech's shot fizzed over the crossbar.
Five minutes from time Swansea took the lead. A quick breakaway saw Montero speed down the right-hand side and lay the ball into the path of McBurnie who converted from close range.
Tom Carroll struck the post for The Swans late on as the 10 men looked to extend their lead, whilst substitute Tom Elliott hit the crossbar with a header right at the death of the game.
Millwall: Amos, Meredith (Bradshaw 86'), Cooper, Williams, J. Wallace, Gregory, Romeo (Elliott 90'), Tunnciliffe, Morison, O'Brien (Skalak 59'), M. Wallace. Subs not used: Martin, McLaughlin, Webster, Karacan.
Scorer: M. Wallace 62'
Booking: J. Wallace
Swansea City: Mulder, Olsson (Montero 66'), van der Hoorn, Fer (Naughton 35'), McBurnie, Celina, James (Carroll 60'), Grimes, Rodon, Roberts, Baker-Richardson. Subs not used: Nordfeldt, Asoro, Carter-Vickers, Dhanda.
Scorer: Naughton 76', McBurnie 85'
Sent Off: Baker-Richardson
Referee: Graham Scott
Attendance: 12,440 (1,134)