Rotorua looked to have the visitors in trouble in the second innings with Tauranga down six wickets for just over 70 runs.
But Tauranga youngster Cameron Neal posted a gritty 45, and a captain's knock by Jono Boult (30) helped to steady the ship, although with eight wickets down Rotorua looked to have the upper hand.
Trent Boult came to the wicket and hung around to combine with Anderson, who had no trouble finding the boundary.
Rotorua showed they have a lethal bowling attack, twice having hat-trick chances during the innings.
Jayvant Dhanjee was the best of the bowlers, taking 3/23, with Prashant Dhanjee removing two Tauranga batsmen.
Although chasing a relatively modest total, the combined Mt Maunganui/Te Puke team were also made to fight for victory by Eastern Bay of Plenty.
Batting first on an outstanding grass wicket at Rex Morepeth Park in Whakatane, the home team were dismissed for 141.
Guest batsman Elliot Timoti top scored with 38, with Eastern Bay stalwart Alex Yates contributing 35 runs. Bay of Plenty quick bowler Tony Goodin took 3/15 with Dale Swan, Daniel Hill and Jeremy Bates taking two wickets apiece.
Ben Guild (47) and Peter Drysdale (31) were the main contributors in the combined team's four-wicket win.
Eastern Bay bowlers made sure the visitors had to battle for the win, with Scott Steward and Joel Mathews the pick with two wickets each.