Harris said Tasman bring a lot of strengths to the table.
"They scrummage and defend really well," he said.
"They also haver Super players in their backline in Marty Banks and Kieron Fonotia who are threats on attack."
"Tasman has been a top four team in the Premiership for the last three years."
Northland has made four changes to the starting lineup, handing a debut to Guy Wood.
The fullback impressed for Mid Western this season but suffered a horrific leg injury.
Now back and firing, Harris said he brings a lot to the Northland side.
"Wood suffered that injury playing for Mid Western, but he has rehabbed well," he said.
"Through the recovery he showed the professionalism he brings to the table.
"He has a quiet calmness, great communication from the back and gives us a left foot kicking option."
The other changes see Tamati Tua in at second five with Jordan Hyland and Solomon Alaimalo moving to the wings.
Wisea Lawebuka moves to the bench, while Jone Macilai was ruled out with a shoulder injury he sustained during the loss to Bay of Plenty.
Dan Hawkins comes into first five after Peter Breen was a late scratching with an achilles injury, and Namatahi Waa comes into the starting lineup at loosehead prop.
Both Breen and Macilai are expected to play against Wellington next week.
Breen's injury paves the way for Solomona Paraki to come onto the bench and potentially make his debut.
Michael Faleafa will return via the bench after recovering from a foot injury he picked up against Auckland in round two.
Kick-off at Trafalgar Park is at 5:45pm tonight.
Northland: Guy Wood, Solomon Alaimalo, Warren Dunn, Tamati Tua, Jordan Hyland, Dan Hawkins, Sam Nock, Matt Matich, Kara Pryor, Tom Robinson, Shane Neville, Josh Goodhue, Phil Kite, Matt Moulds (c), Namatahi Waa. Reserves: Ross Wright, Howard Sililoto, Matt Talaese, Michael Faleafa, Jack Ram, Malcolm MacLeod, Solomona Paraki, Waisea Lawebuka.
Tasman: Mitchell Hunt, Tima Faingaanuku, Kieron Fonotia, David Havili, Caleb Makene, Marty Banks, Billy Guyton, Pete Samu, Shane Christie (c), Tevita Koloamatangi, Quinten Strange, Shannon Frizell, Blair Prinseep, Andrew Makalio, Tim Perry. Reserves: Jesse MacDonald, Kane Hames, Ross Geldenhuys, Jeff Lepa, Ethan Blackadder, Finlay Christie, Tim O'Malley, Trael Joass.
A Look At The Rivalry
Played: 8 Northland wins: 2 Tasman wins: 6
Last match: Tasman 28 Northland 13, 26.09.13 in Whangarei
Last Northland win: Northland 20 Tasman 17, 16.09.12 in Blenheim
Biggest Northland score: 29 (29-34), 15.10.10 in Nelson
Biggest Tasman score: 56 (56-15), 23.09.06 in Blenheim
Biggest differential: Tasman by 41 (56-15), 23.09.06 in Blenheim