THE BACKLINE isn't a place you'd normally find tenacious Bulldog Toby McLean.

And despite doing a stellar job there in round three, you might not see him around there again for a little while.

After missing out on selection in the first two rounds of the season, Dogs coach Luke Beveridge called up McLean with a specific job in mind.

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"I got given a role to tag Lachie Whitfield and go wherever he went," McLean told AFL.com.au.

With Whitfield starting forward, the ball almost became magnetised to McLean across half-back in the early stages with 13 of his 17 disposals coming in the first half.

"Having to tag someone you get a good reference point where you just have to follow where they go," McLean said.

"Whitfield runs really good patterns so you seem to be in the game a lot more than usual."

The role didn't last long with Whitfield's evening cut short after receiving a concussion in the first quarter, but that didn't stop McLean from making an immediate impact in a different role.

After averaging a tick under 24 disposals per game as an inside midfielder in 2018, it was a surprise to some to see McLean not named on the team sheet in the first two games.

Some omissions can be about defensive pressure or wanting a different skillset in a certain position, but for McLean it was just about busting the door down to get back in.

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"There were a few players in front of me that had shown really good training form and I just had to wait my turn," McLean said.

"It's always frustrating when you don't get picked and there's no VFL to play so you can't really show good form.

"I along with everyone else (that hadn't been picked) had to have good training form."

One of coach Beveridge's desires from each player is the ability to play in at least two positions, but unlike pre-conceived switches like Lewis Young and Aaron Naughton, the tagger role is not something that's been in the works over time for the 24-year-old. 

With Sydney not really having clear 'must-tag' player, McLean forecasts a move back to his usual spots in the forward line and midfield on Thursday night.

However, it is a handy ace for McLean to have up his sleeve if pressure for spots gets tight again.