Among the other elites competing include Ben Ruthe (Tauranga), Chris Sanson (Palmerston North), Jonathan Jackson (Auckland) and Liam Scopes (Auckland).
Phil has recorded a brilliant legacy during his running days in New Zealand, with 31 national endurance titles next to his name in a range of disciplines including track, road, cross country and mountain running.
Those titles have also ranged from 3000m to the marathon.
But he will no doubt have his eyes on at least one more title, to try to match his sister's record in Rotorua.
Meanwhile, among the top women competing are Jess Ruthe (Tauranga), Naoko Tsuchiya (Japan) and Erin Furness (Hamilton).
-The runners in the Rotorua Marathon start at 8.20am, next to the Energy Events Centre.
The finish line is also next to the centre.