The Kiwi team dominated the opening four races against the defender (one of the points from those wins was scrubbed out as Team NZ went into the Cup match on -1), revealing massive speed advantage over the US-flagged boat.
But Slingsby, who also heads the team's sailing programme, believes his side have made strong gains over the five-day break.
"We've definitely taken a step forward," said Slingsby.
"We'll find out whether it's enough of a jump [tomorrow]."
Oracle have been targeting improvement in the light air conditions that Team NZ excelled in over the opening weekend of action.
"It's clear they had an edge in speed," Slingsby said.
"But we also did not sail to our potential. Tomorrow we will be faster and try to race smarter and hopefully that will make us an even, or better boat. We're looking forward to getting out there and competing again."
The match could be over by Monday if Team NZ can sweep the four scheduled weekend races to win the series, but could be extended and decided as late as Thursday if Oracle manages to improve its boat speed during this week's five-day break.
With memories of Oracle's incredible comeback in San Francisco still fresh in their mind, Team NZ have worked hard to ensure the break will not be a momentum killer.
The New Zealand boat - Aotearoa - spent two days in the shed undergoing refinements, before the crew got back on the water on Thursday to finetune their crew-work and manoeuvres.
Hunkering down ahead of what could be the biggest two days of their campaign, Team NZ had a short training session this morning before wheeling the boat back in the shed in the early afternoon ahead of what could be the among the most significant few days in the syndicate's history.
