The Lions dominant first-half display was taken advantage by Danish striker Kenneth Zohore, who struck his second goal of the season to give Millwall a first-half lead.
The Wood struggled to get back into the game, and they had few chances to equalise, in which they didn't advantage of, as Shaun Hutchinson scored the second for Millwall and sent them through to the fourth round.
Story of the match
Millwall started the game with an extremely high tempo, in which you'd expect when a Championship side comes up against a National League team.
The bright start came with several half chances from the attacking duo Troy Parrott and Kenneth Zohore of Millwall. Troy came close with a driven effort from 25 yards out, as Zohore had a free-kick bend slightly wide of the post.
Tottenham loanee Parrott had the best chance in the first quarter of the match, with Scott Malone overlapping on his left, he decided to go himself onto his right foot, as he bended the ball inches wide.
Another chance came for Troy as he seemed desperate to find the back of the net, with still no senior goal to his name, the ball was whipped in from a corner, as the ball landed to the feet of Parrott, he cheekily back-heeled the ball towards goal, luckily for the Wood, David Stephens was on the line to clear his lines.
Millwall were dominating the National League side and all their hard work paid off with half an hour on the clock. Wonderful play between Malone and Parrott with a tasty one-two, Malone drove into the area and found the left foot of Zohore, who smashed the ball home from 12 yards to give Millwall the lead.
It was a dominant display from the Lions in the first half, and Gary Rowett must've been delighted with his team's performance. Luke Garrard's men needed to come up with a plan B in the second half, as they didn't manage a shot on target in the first 45.
Within the first minute of the second half, Boreham Wood showed something they didn't once in the first 45. Sorba Thomas flew forward as he tried to square the ball to Kabongo Tshimanga, Millwall defender Jake Cooper was there to clear the ball and prevent the Wood scoring an equaliser.
Millwall were an extremely dangerous threat from corners in this game, and the Lions were inches from making it two. A driven cross from Malone, landed perfectly to the head of Cooper, as he heads against the woodwork to keep Boreham Wood alive.
A minute after Cooper nearly doubled Millwall's lead, he should've been heading back to the changing room. Junior Morias was completely wiped out by Cooper who was already on a yellow card after receiving one 11 seconds into the game, the referee decided against sending him on his way, as the Wood bench were screaming for a second yellow card. A lucky escape for Millwall.
The best chance of the game came for Boreham Wood shortly after and they should've been level. Thomas found the feet of Lincoln City's FA Cup hero Matt Rhead, who nearly lit up the headlines again, but instead he lit up the skies, as he blazed his attempt miles over the bar from around 12 yards out.
A mistake from Wood defender Femi Ilesanmi sent substitute Tom Bradshaw through on goal, with Thomas on his tail, he opted to shoot just inside the area, his attempt was inches wide, if he gave himself more time, he could’ve made it two for the Lions.
In the end, this didn't matter though. As stated before, Millwall were such a dangerous threat on set pieces. With another beautiful delivery from Malone, and a gorgeous leap from centre-half Hutchinson, the Lions made it two, as Hutchinson's header flew into the roof of the net to see Millwall through and destroy Boreham Wood's FA Cup dream.
An extremely energetic and professional performance from Scott Malone see's him win today's man of the match award. His deliveries were fantastic and gave Boreham Wood issues at the back all game long.
A shoutout though to Millwall right back Danny McNamara, who made his debut for the Lions today after three years at the club, he only returned from his loan spell at ST Johnstone last week and played a blinder today, especially in the first half.