North Melbourne assistant coach Darren Crocker says tagger Ben Jacobs began playing in the midfield “out of necessity”, but has now firmly strengthened his standing in the midfield group.

The 23-year-old started the season playing in his customary half-back position, before performing his first ever run-with role in round 11 against Sydney Swans midfielder Daniel Hannebery.

After successfully limiting Hannebery’s impact, Jacobs has been assigned the same lock-down role on Dylan Shiel (GWS), Gary Ablett (Gold Coast), Joel Selwood (Geelong), Dyson Heppell (Essendon) and Tom Rockliff (Brisbane Lions).

Crocker said he was first assigned a tagging role to cover the absence of the Roos’ experienced onballers.

“It came out of necessity because we’d lost ‘Wellsy’ (Daniel Wells), we’d lost ‘Dal’ (Nick Dal Santo) for that period and we didn’t have Andrew Swallow just before that time because of his broken thumb,” Crocker told NMFC.com.au on Friday.

“So we thought, ‘Well, let’s bring him into the midfield but still have him with that narrow focus of really having a strong defensive mindset’, and that’s why we got him to start doing some run-with roles on what we consider to be the opposition’s more dangerous midfielder.”

As part of his weekly preparation for games, Jacobs is assigned his individual match-up on Wednesday and is then required to undertake his own research by watching vision of his opponent.

The 185cm utility then reports back to the coaches later in the week on what he has gleaned and is offered some advice along the way.

“He’s come up on a Friday in the past few weeks and we’ve gone through the vision with (development coach) Jarred Moore and myself on what he’d seen,” Crocker said.

“He would’ve been looking at it not from a holistic perspective but really narrowing his focus on what his opponent was doing in those video clips.”

In their chat, Jacobs, Crocker and Moore set key performance indicators on how to nullify the rival midfielder, which is later reviewed at the start of the week.

“We go through some more vision of what we’ve seen and put that all together so that he’s got some strong focuses going into games,” Crocker said.

“Monday becomes his review, so from those focuses we then review how well he carried out those instructions and executed the plan.”

Crocker said Jacobs had performed each of his tagging roles with aplomb by using his running capacity and power around the contest to his advantage.

The 61-gamers’ effort against the Brisbane Lions last weekend after Dayne Beams was a late withdrawal from the game had particularly impressed the Roos’ coaching staff.

“What was really encouraging was that a lot of his preparation was for Beams and then just before the game he had to change that to Rockliff,” Crocker said.

“Sometimes players can get a bit flustered when things change just before the bounce of the ball, but his ability to be able to change his focus straight onto someone else and have the same strong mindset was really encouraging.”

Crocker said Jacobs was building strong evidence that he could shut down the competition’s most dangerous ball-winners, with his experiences in defence allowing him to follow his opponent all over the ground.

“The beauty of his role is that he can now go into the midfield with a narrow focus on an opponent and if that opponent tries to go to a wing, we’re comfortable for him to go to a wing,” Crocker said.

“And because he’s had that experience of playing down back, if that opponent wants to go and play forward, we’ve got the flexibility of sending Jacobs all the way with him and he’s been able to adjust around that.

“He realises now if he sticks to his task and he executes it really well, it shows everyone else how much he’s invested in the team’s performance and the team’s success.”