Joe Webber was a constant threat down the left edge.
Bay of Plenty turned down a kickable penalty in the 13th minute as they looked to capitalise on their lineout prowess. However Northland remained strong and forced an error from the visitors.
Neither side seemed to be able to break the other's defence until Delaney struck a flat 45 metre penalty into the breeze to extend their lead to 10.
Bay of Plenty furthered Northland's troubles shortly after as winger Monty Ioane sliced through the defence to score under the posts.
Northland fought back after a Dan Hawkins break put them into great field possession. They hammered the Bay of Plenty line until prop Howard Sililoto burrowed over for their first points of the season.
Hawkins added the extras to bring the deficit back to 17-7 with four to go in the half but two costly penalties extended Bay of Plenty's lead to 23-7 at the break.
Northland had much of the early running in the second stanza as they probed the Bay of Plenty line.
Their persistence paid off as replacement loose forward Jack Ram drove over the line to bring Northland right back into the contest.
Rene Ranger showed a touch of class in his return to the Cambridge Blue as he took off on a 70 metre run from a quick tap penalty. After losing the ball, Northland turned the ball over and found an open Matty Wright who gleefully took the space to score under the posts.
The Peter Breen conversion brought Northland back to 23-21 as the crowd began to come alive.
Northland continued their second half surge as Rene Ranger threw a cut out ball which was almost intercepted. Wright claimed possession and found Jone Macilai who scored in the corner to give Northland their first lead of the match.
Breen nailed a sideline conversion to extend the lead to 28-23.
Bay of Plenty began to hammer the Northland line for the last eight minutes of the contest but with a raucous crowd in their corner, Northland refused to relent.
Malcolm MacLeod belted the ball into touch as soon as the siren blared as Northland launched jubilant celebrations as they clinched victory.
Northland 28 (Howard Sililoto, Jack Ram, Matty Wright, Jone Macilai tries, Dan Hawkins 2 con, Peter Breen 2 con)
Bay of Plenty 23 (Tom Franklin, Monty Ioane tries, Mike Delaney 2 con, 3 pen)
Halftime: Bay of Plenty 23-7
