Full-time score from The Den
Justin Skinner's charges made it four wins in five as they swept aside a lack-lustre Eagles side who were taught a lesson in the art of finishing by the rampant Lions.
Just moments after Paris Cowan-Hall had fired over from close range, Martin set the victory wheels in motion with Millwall's opening goal on 17 minutes. Cowan-Hall's cross was blocked by the visiting defence, but the ball fell kindly for Martin, who side-footed home from close range.
The Lions doubled their tally five minutes later, and what a build-up it was too! Martin picked up the ball on the left flank, embarked on a mesmerising mazy run that bamboozled three defenders, before teeing up Upson, who swept the ball over the line with aplomb.
Palace then enjoyed their best spell of pressure in the game with Ben Wynter heading wide of the mark and then lashing off target before eventually getting a foot-hold six minutes before the break. A good move on the left following a short corner culminated in Reis Greenidge forcing the ball over tjhe line from a couple of yards out.
Any hopes the visitors had of getting back on level terms were dashed within seconds of the restart. Intelligent anticipation by Martin paid off handsomely when he punished dithering defending between centre-half Greenidge and goalkeeper David Gregory to poke home Millwall's third goal of the afternoon.
It was 4-1 just past the hour mark when Martin, revelling in a free role behind lone front man and captain Alfie Pavey, worked his magic again, this time picking out Thompson in the penalty area. The midfielder still had plenty to do, and wriggled his way into a central position before rifling home with his right foot.
There was to be no way back for the shell-shocked Eagles, and worse was to follow for them when superb combination play between Martin and Pavey ended with the latter's cheeky backheel to the onrushing Powell, who rammed past keeper Gregory with glee to put the seal on victory with eight minutes left.
Crystal Palace: Gregory, Wynter, Sturgess, Hoare, Phillips, Greenidge, Berkeley-Agyepong, Breimyr, Bissaka, Dreher (Dymond, 70mins), Lokilo (Andrews, 70mins). Subs not used: Perntreou, Coker, Croll.
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