Whaka coach Kopae Irihei said it was always a big game when Rotoiti and Whaka did battle.
"They are the two big players in Rotorua rugby. For the last 10 years it has just been us two carrying the Rotorua flag.
"It is a match both teams really look forward to and normally the Tai Mitchell Shield is at stake as well," he said.
"The winner of [tomorrow's] match will obviously get to hold on to the shield for the rest of the year and, more importantly, the four or five points will just about seal both our fates."
Whaka will almost be out of contention to make the playoffs if they lose tomorrow.
"I don't think it will be [the end of our season], but we will be reliant on other results," Irihei said. "So even now we just have to be sure that we win the rest of our games."
Meanwhile, Rotoiti could still remain in the top four even if they lose, but they will not be resting on that prospect.
There are only four rounds left before the playoffs and all the top sides are under pressure to get results.
Rotoiti have won four games on the trot heading into tomorrow's match,
That included a close victory over their bogey side, Te Puna, last weekend.
Meanwhile, Whaka recently suffered three straight losses but bounced back last weekend with a big win over Opotiki.
Rotoiti coach Dave McLean said: "It will be another tough game again this weekend, but as long as we keep to our systems and patterns we should do all right."
Baywide rugby draw for tomorrow
Premier (2.45pm kick-off): Mount Maunganui v Paroa at Blake Park; Opotiki v Waikite at
Princess Street Reserve; Rotoiti v Whakarewarewa at Emery Park; Tauranga Sports v Greerton
Marist at Tauranga Domain; Te Puke Sports v Rangataua at Murray Salt Stadium; Te Puna v
Whakatane Marist at Maramatanga Park.
Premier development (1pm)
Division One (2.45pm): Arataki v Poroporo at Arataki Park; Katikati v Kahukura at Moore
Park; Marist St Michael's v Ruatoki at Marist Park; Ngongotaha v Judea at Ngongotaha
Domain; Reporoa v Rangiuru at Reporoa; Te Teko v Galatea at Dunderdale Park.
