A sensational 35-yard rocket by James Henry saved Millwall's blushes as Kenny Jackett's side salvaged a point from a dour Den draw.
Henry's magnificent 91st-minute strike denied struggling Swindon Town their third away win of the season and kept Millwall in the Play-Off places.
The visitors had looked to be heading for all three points courtesy of Billy Paynter's 42nd-minute header.
But when Henry picked up the ball on the left in injury-time, the 19-year-old strode forward before letting fly with a right-foot rocket worthy of gracing any stage.
It was an exceptional moment of quality on what was otherwise a largely forgettable night for The Lions.
Jackett made three changes to the side that drew at Stockport on Saturday with Neil Harris, Richard Duffy and Lewis Grabban taking the places of Ashley Grimes, Alan Dunne and Dave Martin respectively.
Perhaps if Adam Bolder had sent his fourth minute header from a Harris cross a yard either side of Peter Brezovan instead of straight into the keeper's hands, it might have been a different story.
Instead, the opening 45 minutes proved painful to watch at times as the out-of-sorts Lions, with the exception of the tireless Jimmy Abdou, struggled to play with any real cohesion or composure.
Admittedly the home side produced the best move of the half with Andy Frampton and Harris combining on the left before the latter curled over a cross that saw Abdou's header blocked on the line by Brezovan on 38 minutes.
But it was Swindon who produced the goods where it mattered most three minutes before the break.
Henry was harshly penalised for a foul on the left and when Michael Timlin swung over the resulting free-kick, Paynter was allowed the freedom of the home defence to pick his spot with a powerful header that gave keeper David Forde no chance.
Millwall huffed and puffed after the restart, but were really not firing on all cylinders.
It was only the introduction of Grimes (67mins) and then Alan Dunne (76mins) that finally saw The Lions begin to produce glimpses of the form that had eluded them for much of the night.
Harris went close on 73 minutes with a low shot that was held at the second attempt before seeing a sublime 76th-minute freekick somehow tipped over the bar by Brezovan.
Dunne picked out Henry on the right eight minutes from time and the latter's low cross flashed across the face of goal, needing the merest of touches to steer home.
Despite Swindon's frustrating time-wasting tactics as the game headed towards full-time, The Lions kept plugging away in a desperate bid to prevent a third league defeat in four matches.
And just seconds after the fourth official had shown four minutes of stoppage time, up stepped Henry to hit his wonder goal.
In fact Millwall could have gone on to win in the dying seconds when a cute reverse pass by McLeod found Grimes on the left. He in turn cut into the area and somehow managed to create space before seeing his floated effort drop a whisker wide of the far post.

Millwall: Forde, Duffy (Dunne, 76mins), Frampton, Bolder, Craig, Whitbread, Grabban (Grimes, 65mins), Abdou, Harris, McLeod, Henry. Subs not used: Pidgeley, Barron, Laird.
Booking: Grimes (89mins)
Scorer: Henry (90+1min)

Swindon Town: Brezovan, Smith, Vincent, Timlin, Ifil, Robson-Kanu (McNamee, 70mins), Kanyuka, Amankwaah, Paynter (Sturrock, 85mins), Cox, Greer (Lescinel, 78mins). Subs not used: Smith, Razak.
Bookings: Greer (47mins), Smith (59mins), Cox (84mins)
Scorer: Paynter (43mins)

Ref: Pat Miller
Att: 7,104 (away 351)