Skipper Alex Wakely says last week's joint training session with Saints was an eye-opener for the Northants squad.
The cricketers headed to Franklin's Gardens to train with players from the town's Premiership rugby team and were put through their paces with a range of rugby-related drills and games.
The Gardens has hosted Northants regularly over the past few years, helping the Steelbacks celebrate their Vitality Blast wins in 2013 and 2016.
But this was the first time that a joint training session had been held in this way.
"Over the years we've had a decent relationship with the Saints," Wakely said.
"In the past we've come to Franklin's Gardens and had a bit of fun, but this was a proper fitness session.
"It's nice when we can help each other out. The Saints boys come and watch us and there are four or five of the cricket lads who like their rugby and go and watch on a regular basis.
"It was a pretty tough session. When you're watching on TV you don't get a full appreciation of how physically fit and tough rugby players are.
"When you're up close you see they're big lads, but they're also fit with it.
"For me we're lucky to have a town with three major sports teams so it's good to make the most of it."
The Northants skipper, who renewed his contract at the club earlier in the winter, says that there is a new and improved focus among the players ahead of the 2019 campaign.
"Last year was disappointing for us," Wakely said. "We've gone back to the drawing board and want to put things right this year.
"There's an appreciation that we've got to work harder, especially on our fitness, and on the cricket things as well people have been working hard.
"We know that every year the game gets harder, the game gets stronger, so we have to stick to that and work harder."
As well as having the likes of Wakely, Josh Cobb, Nathan Buck and Rob Newton put pen to paper on new deals, Northants have also confirmed the signings of international stars Jason Holder, Temba Bavuma and Faheem Ashraaf for portions of the coming season.
"Signing someone like Jason Holder is a massive coup for the club, especially with what he's done in the Test series against England," Wakely said.
"He's someone I can learn from as a captain and the players will be looking forward to it, too.
"I'm certainly excited by the squad.
"But it also shows where the club want to go; we're not just prepared to sit there and let other clubs beat us, we want to be competitive and winning trophies.
"There are a few people in the changing room who have experienced winning silverware and we want to get back to winning ways."