AIDEN O’Brien scored a brace and Ben Thompson and Fred Onyedinma got their first goals of the season as Millwall came from behind against Barnsley to move into the fourth round of the FA Cup.
The Lions struck three times in 14 minutes after the break and Barnsley’s Joe Williams was sent off in during the same period as Millwall eventually comfortably cruised to victory.
After Tony Craig shot over the bar from a corner in the fourth minute, the Tykes went in front from their first real attack when Brad Potts slammed the ball past David Martin from Adam Hammill’s cross.
Tom Bradshaw saw his left-footed flick deflected over before O’Brien headed just wide of the near post from Shaun Williams’ cross.
Millwall levelled in the 35th minute through O’Brien, and he could have added a second almost immediately when he flicked the ball over goalkeeper Adam Davies but Dimitri Cavare got back to clear.
The Lions should have been ahead just before the break when O'Brien sent a cross into the corridor between Jason McCarthy and Davies for Jed Wallace, who prodded across goal but the ball went wide.
Thompson made it 2-1 two minutes into the second half when he fired home from close range and then Barnsley were reduced to 10 men, Williams given a straight red card for a late tackle on Wallace.
In the 56th minute the tie was all but over as O’Brien fired a low shot into the corner from outside the box, and five minutes later Onyedinma put Millwall three goals ahead.
George Moncur shot straight at Martin late on, but there was little fight left in Barnsley as Millwall progressed to the last 32 for the second successive season.
Onyedinma and Thompson get chances to impress
Millwall boss Neil Harris made six changes from last Monday’s league defeat to Norwich, but it was still a strong side, with seven first-team regulars.
Of the four others, Onyedinma was probably the one with the most to gain, given Martin, Craig and Thompson will only realistically start if there is an injury.
Onyedinma started up front alongside Steve Morison. He looks far more comfortable as a forward playing on the last line than he does confined on the right.
There was a neat twirl away from Williams early on before he anticipated Morison’s flick-on but his shot was deflected over. When Millwall equalised, Onyedinma made a motion to try to control the ball but O’Brien wasn’t put off and drilled home low with his left foot. In the lead-up to the goal, it was a superb tackle from Craig that gave Wallace the chance to move forward and cross from the left. Harris could also take credit for having switched his wide players minutes before.
Thompson then upstaged Onyedinma when he finished low for his first goal since April 2016, O'Brien providing the assist.
But not to be out-done, Onyedinma grabbed his chance from Morison’s brilliant flick to chip neatly past Davies with his left foot.
Cup magic fails to draw crowd – but frustration eventually turns to enjoyment
The fact that it was Barnsley and the fifth meeting between the sides in two-and-half years combined with neither manager attempting to drum up any hype during the week was reflected in the attendance.
The last thing it needed from the hosts’ point of view was an early goal for the away side and then for straightforward passes to go astray, which led to some squabbling on the pitch between Millwall players.
Craig had been guilty of squandering possession twice, but then his tackle lifted the crowd and O’Brien scored his third of the season. That at last was something for the majority of the 5,319 at The Den to cheer about.
O’Brien was arguably Millwall’s most influential player, and after he added his second – a nonchalantly excellent effort – and the Tykes' Williams departed, the result was never in doubt. From an afternoon that looked destined to be a frustrating one, the home fans ended the game cheering every pass by their players.
Attention turns to fourth-round draw
It’s all about getting through in these earlier rounds and doing so without picking up any injuries.
Harris probably would have preferred to rest Shaun Hutchinson and Jake Cooper, but Craig was the only real option to come in.
All eyes will now turn to Monday night’s draw and the hope that one of the top Premier League sides is paired with Millwall’s ball, or that the Lions get a home tie against beatable opponents.
A draw was avoided, and Harris was able to rest George Saville and James Meredith, after both played every league game this season.
The only concern was Morison going to the touchline to have a word with Harris, before the striker went off and Lee Gregory came on with 18 minutes left.
But it was a job well done – eventually – as Millwall stopped their five-game losing streak against Barnsley.
Image: Millwall FC