Tanak is fighting to stay in the World Rally Championship title race, with the 21-year-old Rovanpera needing to beat the Hyundai driver by just eight points to become the youngest world champion with two rounds to go.
Kiwi Hayden Paddon remains on top of the WRC2 category and ninth overall, with a 1m37s advantage over Supercars champion Shane van Gisbergen.
In just his fourth WRC rally of the season, Ogier finished the morning's three special stages in fifth, 9.7 seconds off the pace of Tanak.
But it was in the afternoon that the veteran showed his class, with heavy rain periodically belting the Raglan roads.
Ogier swept the field in special stage five on the Whaanga Coast 2 course, ousting second-placed Evans by 8.4 seconds and leaving Tanak 17.2 seconds in his dust.
That gave him a 1.3-second overall lead which he extended to 5.6 seconds by placing third in stage six.
However, Ogier lost a chunk of his rear spoiler to a tree branch on the Te Akau South 2 track, slowing him down in the final stage of the day.
The Frenchman struggled to keep pace with Tanak on the Te Akau North 2 track, with Tanak surging back into the lead, winning the stage by 13.3 seconds.
Ogier said the aero damage on the back of his Toyota badly hampered his efforts to maintain the lead.
"Without wings on such a fast stage - I did what I could but it was not the same."
Paddon had a typically smooth day on his home track, winning all six stages in the WRC2 category to sit ninth overall, ahead of Italian WRC1 driver Lorenzo Bertelli.
But the Hyundai driver is not satisfied, mentioning to co-driver John Kennard he was "driving like nana" on special stage seven.
Paddon says they sustained some damage and repairs are in order.
"We've got a bad tyre on the right rear and a bad tyre on the left front so we're managing it. It makes it interesting because sometimes it snaps in when you don't expect it so you've got to pull yourself back and really stay on the line."
Van Gisbergen is 12th overall and says his "no expectations" approach is working wonders.
"I'm just having a ball and living my dream. Looking forward to the next two days, hopefully get better and tidy up some mistakes."
Two-time New Zealand champ Ben Hunt was forced to retire after spinning out on the final stage of the day.
Rallying continues in Puhoi through the Kaipara Hills on Saturday with the return to Jack's Ridge in Whitford on Sunday.