Conversely, Robinson's Bay counterpart, Richard Gillespie, took more shots than a tequila bar to keep Waitakere to 1-0 at halftime after captain Jake Butler opened their account in the 41st minute after latching on to an Allan Pearce delivery.
The first half yielded a staggering 13 clear-cut scoring opportunities for the O-League campaigners.
McIvor, who ran on in the second spell, felt the Bay enjoyed more possession and territory in the latter half to create opportunities but their strikers, minus injured Milos Nikolic, didn't see much in the 18m box to write home about.
The crushing blow came in the 78th minute when referee Peter O'Leary waved on a Waitakere foul after his assistant pinged an attacker for grabbing defender Alex Barlow's shirt.
Two phases later Barlow brought down Pearce to concede a penalty that Pearce scored on his second attempt from the spot kick after keeper Gillespie parried the ball but couldn't snare it.
"I thought it was a dubious penalty," McIvor lamented.
The Bay went through the motions for the last 15 minutes as adroit Fijian international Roy Krishna put the visitors out of their misery with a 3-0 lead with seven minutes to go.
Perhaps the radical move from Chandler to play 121-game new signing Adam Cowan as centreback gives a candid snapshot on what the Bay mindset was to the game.
Explained McIvor of the Waitakere United Chatham Cup-winning captain: "We signed him [Cowan] as a midfielder but he has played in the centreback position before."
Youngster Tom Biss and English import Stephen Hindmarsh stoked the engine room for the Bay but, bar keeper Gillespie's performance, it seemed the post-mortem on the Bay performance was below par.
"Across the board, if you ask any of the Bay players, they'll tell you they didn't play up to the standard required," McIvor said.
The Bay now host Youngheart Manawatu at the Bluewater Stadium, Napier, the following Sunday in a 2pm kick-off.