Derby County picked up their first away point of the Championship season but were denied victory in a dramatic late finish when Millwall substitute Mihailo Ivanovic rescued a draw with a fine individual goal.
The Rams, who had won four out of five games at Pride Park and lost all four away fixtures, seemed set for a first draw in 10 league matches this season after withstanding considerable pressure to keep the hosts at bay.
But Jerry Yates then headed home from a corner for his first Derby goal to put them ahead with their only attempt on target on 78 minutes.
The out-of-form Lions responded impressively, with Ivanovic showing great composure to run through and fire them level, and finally break down a stubborn and well-organised defence.
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A point was the least Millwall deserved on a frustrating afternoon, but they have now won just one of their past six league fixtures and are just two points above the relegation zone
And their recent tendency to fail to turn decent performances into wins will once again rile boss Neil Harris.
The Lions controlled the first half and most of the second period without reward and had the better chances, notably when Macauley Langstaff fired a shot against the inside of the post before the break.
Ryan Leonard, George Honeyman and Duncan Watmore also all had opportunities for the hosts white Derby barely threatened and did not force keeper Lukas Jensen to make a save.
Yates did send a header wide in a rare foray forward, but Derby, who remain 12th, defended resolutely and with great discipline despite having to replace the injured Ryan Nyambe with Kane Wilson.
With the game looking destined for a scoreless draw, Yates headed in from an inswinging corner, before Ivanovic struck with five minutes remaining.
Lions 'created enough chances to win' - reaction
Millwall boss Neil Harris told BBC London:
"From the outside it might look like a good point, coming from behind and rescuing a point but I'm disappointed.
"It's another goal conceded from a set-piece so we need to have a better mentality.
"I'm fed up with talking about the same things - not being dominant in both penalty areas.
"We created enough chances to win the game.
"On the flip side I'm absolutely delighted for Mihailo [Ivanovic - goalscorer] - he's moved abroad, away from his family to come over here and follow his dream and it's vital that he's got his first goal."
Derby County boss Paul Warne:
"We told the lads about their threats – they put a lot of throw-ins in the box, a lot of free-kicks in the box, a lot of corners in the box which you have to really stand up to, and I thought we did.
"I thought we were really well organised, won a lot of first contacts, so I felt like we nullified it well and I didn't think they were going to score, but unfortunately, randomly, something happened and we conceded.
"I thought we looked quite resolute, they did have a really good chance first half. I thought we'd won a penalty – I didn't think it was offside – and then I just thought at times we were really dangerous on the counter.
"We had a couple of really good chances that I'd like us to take, obviously, but maybe over the course of the play, a draw is a fair result."