The loss to Auckland was felt heavily in the casualty ward, with lock Josh Goodhue and loose forwards Michael Faleafa and Dan Pryor suffering injuries that will render them unavailable for selection.
Goodhue is missing due to concussion, but is already on the right protocols involved with the injury. His timeframe is not fully clear.
Harris said Faleafa's and Pryor's injuries were more severe, with Pryor likely to miss the rest of the Mitre 10 Cup campaign.
"Pryor is highly likely gone for season with an ACL injury. He landed on his knee, and it has gone the wrong way. He's seen the surgeon and is definitely out this week, but it's not looking too good," he said.
"Faleafa has a suspected broken foot. He will have more x-rays to check damage. It's looking to be two to three weeks, at least."
Looking to Otago, Harris said they are wary with their ability to play well at home and will continue to look to improve the set piece.
"They play at home well. There are little nuances about the stadium and they know it well. They utilise high ball well and have terrific support plays on attack which test scrambling defence. It's second-to-none," he said.
"Game-plan wise, it's not too different. We want good set piece ball, replicating our scrum against Auckland and we are desperate to get lineout going well again.
"Our intent is to improve. If we get to the gain line, we can use our strike moves."
The match will be a homecoming for first five Peter Breen, having played 40 games for the southerners.
Six changes have been made to Northland's starting lineup: captain Matt Moulds and flanker Kara Pryor return from injury, Matt Matich comes in off the bench for Dan Pryor, Howard Sililoto gets a start at prop, Jordan Hyland goes back to second five and Wisea Lawebuka will start on the wing.
Otago v Northland, Forsyth Barr Stadium, tonight, 7:35pm.
Northland: Solomon Alaimalo, Wisea Lawebuka, Warren Dunn, Jordan Hyland, Jone Macilai, Peter Breen, Sam Nock, Matt Matich, Jack Ram, Kara Pryor, Shane Neville, Josh Larsen, Phil Kite, Matt Moulds (c), Howard Sililoto; Reserves: Jordan Olsen, Namatahi Waa, Matt Talaese, Epineri Uluiviti, Aorangi Stokes, Matty Marwick, Dan Hawkins, Tamati Tua.
Otago: Michael Collins, Fa'asiu Fuatai, Matt Faddes, Sio Tomkinson, Jack Wilson, Fletcher Smith, Josh Walden, Paul Grant (c), Naulia Dawai, Sione Teu, Blair Tweed, Tom Franklin, Hisa Sasagi, Sam Anderson-Heather, Aki Seiuli; Reserves: Liam Coltman, Craig Millar, Donald Brighouse, Tom Rowe, Hame Toma, Kaide Whiting, Scott Eade, Tony Ensor.
