"I am bloody rapt to get it (100th cap). It has taken a lot of hard work, so thanks to everyone for supporting me," Retallick said immediately after the game.
"The victory would have been good but just too many unforced errors and we seem to be letting teams off when we get down their end and they seem to capitalise.
"That has been the story for us this season.
"We thought they fan out a fair bit so we thought we could go through the middle. We got down there okay but we knocked the ball on a couple of times and let them off the hook.
"Certainly something to work on during the week."
The turning point came with Harbour leading 13-10 late in the first half. The Steamers attacked superbly from deep, holding the ball for 13 phases up to Harbour's line but with a certain try on they spilled the ball forward.
Harbour took the chance to counter well which ended with Tevita Li scoring nearly 100 metres from the turnover.
It gave Harbour a crucial 10-point lead at the break that was the winning margin in the end.
Li scored again straight after the restart to extend the lead to 15 before Steamers fullback Isaac Te Aute showed his speed to gas the Harbour defence and set Monte Ioane up for a top try in the corner. Hollinshead converted from touch to close the gap to 25-17.
But a minute later Matt Vaega scored for Harbour after a high ball was spilled then Nick Mayhew added to the agony when he scored his first try for Harbour.
Replacement forwards Henry Stowers, Joseph Royal and Jesse Parete all scored late tries for Bay of Plenty but it was too little, too late.
The season is not over with Manawatu and Hawke's Bay to come but against Harbour the lack of accuracy, composure and a bloody-minded attitude to win was hugely disappointing in a game with so much riding on it.
North Harbour 44 (Tevita Li 2, Chris Vui, Matt Vaega, Nick Mayhew, Matt Duffie tries; Bryn Gatland 4 con, 2 pen) Bay of Plenty 34 (Teddy Stanaway, Monte Ioane, Henry Stowers, Joseph Royal, Jesse Parete tries; Dan Hollinshead 3 con, pen) HT: 20-10
