AN outstanding Millwall performance was capped by an Aiden O'Brien goal as league leaders Leeds United were deservedly beaten at The Den.
It was Millwall's second win of the season in the league, and at least at home they are finally getting the rewards their efforts deserve.
Millwall's defence was superb, some of their attacking interplay a delight, summed up in the 73rd minute when Jed Wallace flicked the ball over the Leeds defence to Fred Onyedinma, who helped it to O'Brien to score his second goal of the season.
This was arguably Millwall's most dominant performance of the season, against a side that came into the game top of the league, having not conceded since the opening day.
Thomas Christiansen reacted to his side's problems by taking off his two attacking wide players at the break. It was indicative of the way the game had gone for a side that had scored more goals in the Championship than any other before Saturday.
Millwall should have won by more, and had George Saville, who was superb again along with every one of his team-mates, not skied a shot from eight yards with five minutes left the score-line would have better reflected how good the hosts were.
As it was, they had to be satisfied with just one goal, but three points against this calibre of opposition will give them so much belief.
With Lee Gregory suspended, Lions boss Neil Harris handed Onyedinma a start after six substitute appearances in the league this season. O'Brien was back on the left wing after his ban, with Shane Ferguson dropping to the bench.
O'Brien was one of the first half's most influential players, along with Onyedinma and Shaun Williams. Twice Williams fired long-range efforts towards goal in the first half, but one was deflected for a corner and Felix Wiedwald had to tip his 35-yard drive over the crossbar just before the break.
Wiedwald had been less sure after seven minutes when he spilled Conor McLaughlin's shot, and Morison rammed home the rebound in front of the Leeds fans. Celebrations were halted, though, as the linesman's flag had gone up.
That didn't put off the home side, who dominated the opening 45 minutes. Four minutes after his disallowed goal Morison pulled a ball across goal but there was no Millwall player to take advantage.
That was a trend in the first half, and it must have been hugely frustrating for the watching Gregory.
That's not to say Onyedinma was not proving an adequate replacement. He was a nuisance to the Leeds defence, and when Conor Shaughnessy was booked for fouling the attacker late in the half it well overdue. Certainly, after the failed Gregory red-card appeal, it would have fed the general sense of injustice this season when Vernon Anita did not go in the book for an earlier blatant foul on Onyedinma, who was bearing down on Pontus Jansson and Sahughnessy.
Anita endured a torrid first half. It was evident from early on he couldn't match Wallace's pace. In the 37th minute Wallace brilliantly beat two defenders on the right but his flashed cross was left unfinished. Two minutes before the break, from a pre-planned set-piece, Williams found Byron Webster on the right edge of the box to head towards Morison, whose nodded effort was pushed around the post by Wiedwald.
Leeds, on the other hand, had offered so little as an attacking threat. As well as that, their wide players, Pablo Hernandez and Ezgjan Alioski, weren't offering anything defensively, either, which was allowing O'Brien and Wallace to be so influential.
It wasn't much of a surprise that Hernandez and Alioski didn't reappear for the second half, Kemar Roofe and Stuart Dallas coming on.
It did little initially to stem the tide of attacks towards the visitors' goal. In the 50th minute, after Leeds had escaped a couple of near-misses, Shaun Hutchinson connected left-footed inside the box but Wiedwald stretched out his left leg to prevent his side going behind.
The goalkeeper was sticking out his right leg soon after, but needed the base of the post to come to his rescue as Wallace was denied.
Leeds had yet to test Jordan Archer, though Millwall's defensive vulnerability to a counter-attack was tested when Dallas latched onto a loose pass. Williams tracked the move to make the crucial interception.
After Eunan O'Kane was then booked in error following his midfield partner Kalvin Phillips' foul on Onyedinma, Saville found Wallace in space on the right. His cross fell to the feet of Morison, who had to wait a fraction longer than he would have wished for the ball to come down, and Wiedwald was in the right place to bat away the striker's effort.
When it seemed like it would be another one of those days this season, O'Brien found himself in space six yards out to finally put Millwall ahead. It was typical of O'Brien to be following the play up and lurking in that kind of space.
Equally as impressive as how Millwall went about getting in front was how they completely limited Leeds in attack. Archer didn't have a save to make.
It was yet another statement that will make other sides take notice.
Image: Millwall FC