John Barker’s first major task as interim Carlton coach will be extracting maximum effort from the battered Blues, a quality which has been notably lacking in their sorry start to the AFL season.

Three days after record-breaking coach Mick Malthouse was sacked following a very public falling-out with the Carlton board and executive, the bottom-placed Blues take on Sydney at the SCG on Friday night.

To make a daunting task even tougher, they will do so without two of their few top-line midfielders in Chris Judd and Bryce Gibbs, who are both unavailable due to injury.

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For Barker – who is set to be among the candidates to replace Malthouse on a permanent basis from 2016 onwards – the message to the players will be simple.

“We know that there have been some issues with our effort and we know it’s one of the core components of footy,” Barker told reporters on Thursday.

“It’s really just to drive some spirit and some energy back into the place.

“We don’t think things are going to turn around overnight.

“We’re realistic about that and we know that the top effort that we’re talking about, we need to work at it and that will take time.”

At least in the short term there will be no sweeping changes to a game-plan which has delivered just one win in eight matches.

“It doesn’t matter what game-plan you play with, if you don’t bring effort, a baseline of effort, it’s null and void,” said the 40-year-old Barker, who joined the Carlton coaching staff in 2011.

“We’ll keep the expectations with the players very minimal and we’ll keep the focus very minimal.

“It’s been a really big week for them and we’ve got a fairly solid job trying to manage their mindsets.”

Barker paid tribute to fellow coaching panel member Robert Wiley and star utility Dale Thomas, the two people at Carlton who were closest to Malthouse.

Wiley was the first person to approach Barker on Tuesday and pledge his full support once he was given the nod to be caretaker coach for the remainder of the season.

Thomas played under Malthouse at Collingwood and Carlton.

“Daisy obviously had a great relationship with Mick but what Daisy is, he’s a competitor,” said Barker.

“We know that tomorrow night, when we get out there he’ll be giving it his all.”

– AAP