Clearing that hurdle, the Taniwha were put through vigorous drills at training yesterday as they worked hard for the remaining spots in the playing side to travel to Hawke's Bay on Saturday morning.
"It was a bit of a physical training at the start," Harris said of yesterday's training.
"There's a few spots up for grabs still and the boys know that. We'll look to name a team on Wednesday internally and really hook into it."
With less than a week left, Harris said the Waikato fixture was a fitting end to the pre-season.
"It sort of helped us with selection for sure. We identified players who are working in the direction that we want them to and ones that are a little more behind it."
Back in the squad this week is Highlanders loose forward and Northland co-captain Dan Pryor.
At training yesterday, Pryor got through some drills but was reduced to light contact as he is still on the mend after dislocating his elbow against the Chiefs during the Super Rugby season.
While Harris said Pryor "definitely won't be playing Hawke's Bay", he did confirm that, all going well, Pryor and first-five Dan Bowden could make a return in week four of the ITM Cup if their rehabilitation programmes went well.
Also back in the Northland squad and training yesterday was Jack Ram, who is fighting fit off the back of his stint with Tonga at the Pacific Nations Cup.
Tonga name their Rugby World Cup squad in the next few days so Ram could be a late omission from the opening round.