Two second-half penalties from substitute Ryan Manning completed a late turnaround as Rotherham defeated Swansea 2-1.
The visitors dominated proceedings for much of the match but paid the price for not adding to their goal tally when on top.
Swansea arrived at the New York Stadium looking for a third straight win and certainly looked the in-form side for the vast majority of the match.
They took the lead on 25 minutes when livewire Daniel James scampered down the left and crossed for Oli McBurnie to finish neatly past Marek Rodak.
The visiting side continued to create more of the chances, with James blazing over and Rodak having to block Bersant Celina's effort.
Rotherham's sole effort of a frustrating half came from Semi Ajayi, whose header was gathered by Kristoffer Nordfeldt.
The Millers made a change at half-time, with Manning brought on for the ineffective Kyle Vassell, but it was again the visitors who started the brighter.
Roberts found space down the right and crossed for Leroy Fer but his side-footed effort was kept out by Rodak.
Jay Fulton was the next to come close. The midfielder was given far too much licence to roam forward but fired over the bar.
Another Rotherham substitution failed to change the momentum of the game as the Welsh side continued their dominance, with Celina firing narrowly wide.
Rotherham still had a sniff and their best hope looked like coming from a set-piece, with Manning's long-range free-kick pushed out by Nordfeldt.
Paul Warne brought on the physical presence of Jamie Proctor for the final 15 minutes and it paid off as he was felled by Nordfeldt for a penalty.
Manning stepped up on 78 minutes and slotted in his third spot-kick of the season.
Rotherham's belief instantly grew as they suddenly looked the side more likely to find a winner - and got the chance to do so from the spot again on 86 minutes.
A short free-kick was played to Will Vaulks, whose powerful shot was adjudged to have been handled by Fer.
Manning again stepped up and fired into the top corner to seal the turnaround.
The Millers kept hold of the ball throughout five minutes of added time to record a memorable win.