Within 15 minutes the hosts had doubled their score when Luis Corrales ran on to a good ball from David Mulligan and snapped a great volley for a richly deserved goal.
A reflex save from Matt Borren kept the score to two at the break.
Second-half goals to Mulligan, from the spot after Corrales had been fouled in the penalty area, Emiliano Tade and debutante Stephen Carmichael summed up what had been a good day for the home side.
"No injuries, no problems," was coach Ramon Tribulietx's succinct summary. "I thought we played well with the amount of possession we had. I'm sure a lot of the players had one eye on the trip but, having said that, there were some good goals."
Manawatu coach Stu Jacobs was philosophical.
"A result like that shows you the gulf between the top teams and the group below ... We have to put that behind us and look ahead. We have to get points off teams around us.
"You know when you come here you have to work hard. It wasn't made any easier when we learned on Wednesday we wouldn't have Seule Soromon."
Waitakere stayed firmly in the championship race with their away win over Waikato. With Auckland City missing at least the next round on December 11 while on international duty, Waitakere will have the chance to join them at the top of the table and then use "the points on the board are better than games in hand" theory.
Handed an own goal in the 27th minute, Waitakere took the lead and doubled that six minutes before halftime when Roy Krishna scored.
Krishna turned provider for the third goal when he threaded a pass through to Ryan de Vries to bang home early in the second half.
Captain Jake Butler stretched the lead to four seven minutes from time when he got on the end of a Ross McKenzie cross. The last say was with the hosts, however, with Harry Edge snatching a late consolation.