| Venue: The Den
|Armstrong 6, 24; Lameiras 19, O'Brien 76|
COVENTRY did all the damage inside the first 24 minutes to inflict a devastating defeat on Millwall at The Den.
After Lee Gregory had missed a penalty just four minutes in, two goals from Adam Armstrong and a Ruben Lameiras strike put the Sky Blues three up at the break.
Jim O'Brien added a fourth with ten minutes left to make it an utterly depressing afternoon for Neil Harris' side.
Coventry boss Tony Mowbray had spoken before the game about weathering an early Millwall storm before settling down to play a passing game, and that's exactly how it turned out as his side made it two league wins in a row.
Millwall were simply much too naïve after Gregory's penalty miss, handing the midfield initiative to the away side and they didn't hesitate in taking maximum advantage.
Armstrong had given notice last week of the damage he can cause in behind defences with his pace, but Millwall seemed not to heed the evidence as they persisted with a high defensive line in the first half.
The Lions also looked like they didn't know how to deal with Coventry's formation, with James Maddison a really dangerous presence behind the on-loan Newcastle forward.
Millwall will have to consider their approach to the game, but will have little time to make the necessary improvements with Barnsley visiting The Den on Tuesday.
As expected Harris stuck with the side that won 2-1 at Shrewsbury last weekend and that decision looked like it was going to be immediately justified three minutes in.
Lee Martin picked up the ball in the inside left channel to feed Mark Beevers whose shot was spilled to the feet of Gregory by Coventry keeper Lee Burge.
There didn't look to be much contact as Gregory went down, but referee Andy Woolmer didn't hesitate in pointing to the spot.
The striker went to the same side as he had last Saturday but this time, at a nice height, Burge palmed the ball away for a corner.
If Millwall fans were stirred by the bright start, that was as good as it got as they watched their side run ragged for most of the rest of the first half.
Coventry went ahead after just six minutes when Armstrong, such a quick and menacing player, picked up a loose ball 40 yards out and, spotting David Forde off his line, expertly chipped the keeper for his third goal in two league games.
The home side were desperately struggling to get to grips with Coventry's slick midfield trio of John Fleck, Romain Vincelot and Maddison and when the latter engineered some space on the edge of the box on 19 minutes he played a sumptuous though ball to Lameiras.
The right winger had an ocean of space to cut back inside Beevers and he beat Forde at the near post to put his side two up.
If that was a bad goal to concede the third, on 24 minutes, was worse.
With Millwall keeping a high line, Lameiras delayed a pass to Armstrong before releasing the striker and the on-loan Newcastle youngster raced away unchallenged to lift the ball over Forde.
The closest Millwall came in response was a speculative Shaun Williams drive from 25 yards that scraped the outside of the post with Burge beaten.
Harris brought on Shane Ferguson and Ben Thompson for Beevers and Martin at the break and there was a marginal improvement at the start of the second half.
Still, Millwall created nothing clear-cut; Thompson's shot was well saved by Burge before the midfielder found Morison in the box, but his volley didn't have enough on it to trouble the keeper.
Harris introduced Paris Cowan-Hall with 14 minutes left but it was Coventry who added a fourth, Jim O'Brien finishing well after combining with Marcus Tudgay.
And Millwall's misery was summed up three minutes from time when Gregory somehow contrived to miss after Morison's cross had found him inches from the Coventry goal-line.