North Melbourne utility Ben Jacobs' encouraging development as a defender in the second half of 2014 has earned him a new one-year deal that secures his future at Arden Street to the end of next season.

Jacobs, 22, has spent the past two seasons at North after crossing from Port Adelaide at the end of 2012.

The No.16 pick in the 2010 national draft played just seven games in his first season with the Roos, spending most of his time in the midfield.

Jacobs then had a slow start to 2014, playing just three of the Roos' first 13 games, but he turned his season around after switching to the backline.

Recalled for the Roos' round 15 clash with the Brisbane Lions, Jacobs played 11 of the Roos' final 12 games, including two of their three finals.

The only game he missed in the run home was the Roos' semi-final win over Geelong, when he was the unlucky player to make way for Brent Harvey's return from suspension.

North senior assistant coach Darren Crocker told that Jacobs had taken a big step forward in 2014.

"Last year and even throughout the pre-season, Ben was trying to work his way into our midfield and that was always going to be difficult for him because we have a pretty strong midfield," Crocker said.

"When that didn't pan out for Ben he basically asked, 'What role is there that's actually going to give me an opportunity to play every week if I perform?'

"At that stage, we were screaming out for a guy who could play across half-back as a shut-down defender on crafty opposition forwards, but also give us a little bit of rebound with his run.

"So Ben identified that there might be an opportunity there and then he just went for that role. He was in and out with it a little bit early, just trying to get used to it.

"But in the end he's played some pretty consistent footy down back and taken some pretty big strides as a player."

Jacobs spent time in defence in his two seasons at Port Adelaide, but Crocker said the former Sandringham Dragon had still had to learn to become a "hard-nosed defender" this year.

"You want to defend first and then a lot of your attacking game will just flow from there," Crocker said.

"We know that Ben can be a penetrating kick, he can run well, but first and foremost when you're playing down back you've got to be able to play that role of shutting out the opposition's dangerous forwards.

"Once he got that and once he learned about the way we want to move the ball, especially in the back half, I think it came together a little bit more for him."

Crocker said Jacobs still had "enormous" scope for improvement and, more importantly, had the drive and ambition to realise his potential.

"He's only been with us for two years now. He's still learning a different role and his development in that role is still really, really at an early stage," Crocker said.

"With a pre-season of training as a half-back, of playing on guys like Lindsay Thomas throughout the summer, it's only going to improve him.

"Ben's a very driven and ambitious young man. He really wants to succeed, he really wants to make the most of an AFL career that's right in front of him.

"So he's willing to do whatever it takes, whether it's his diet, his training, or committing to and learning what his role requires.

"He's the type of guy who won't leave any stone unturned in trying to get there, that's for sure."