CARLTON great Robert Walls has launched a spirited defence of embattled Blues coach Brett Ratten, saying his coaching record compares favourably to those of Mick Malthouse and Mark Thompson at similar stages of their reigns at Collingwood and Geelong.

Ratten has come under increasing fire following his side's shock loss to Gold Coast at Metricon Stadium on Saturday night - a defeat that extinguished Carlton's finals hopes.

Malthouse has been linked to the Carlton position and on Sunday insisted he still had the energy levels needed for senior coaching.

But Walls believed the Blues' board should honour Ratten's contract, which has a year to run, pointing out that Ratten's winning rate of 53.1 per cent after five completed seasons was superior to Thompson's (48.75) and Malthouse's (47.8) after seven seasons.

He didn't count the six losses that started Ratten's coaching career at the end of 2007, when he took over as caretaker from the sacked Denis Pagan, because he believed the Blues "didn’t want to win", preferring instead to angle for No. 1 draft pick Matthew Kreuzer.

"Collingwood gave Malthouse 11 years to win a flag; Geelong gave 'Bomber' until his eighth season to win a flag," Walls told SEN on Monday morning.

"People think, 'Oh, these are wonderful coaches' (but) Malthouse coached the longest of any person ever before he got that premiership at Collingwood. He had six years at West Coast after they'd won their last flag there, and then 10 years at Collingwood.

"Why isn't Malthouse coaching today? (Collingwood) believed he'd run his race.

"When they had the agreement with Malthouse and (Nathan) Buckley, they very nearly sacked Malthouse and let Buckley have the job (at the end of 2009)."

During the term of the so-called 'Kirribilli Agreement', in which Buckley was an assistant to Malthouse for two seasons, the Magpies won the 2010 premiership and were runners-up last year.

Walls said Ratten was a better coach now than he was 12 months ago because he had been 'grilled' and' tested' and had come through it "amazingly well".

He lay much of the blame for the loss to the Suns on the Carlton players, who he said "should hang their heads in shame".

Walls also said the Blues should announce their coaching plans next Monday, after their final-round clash with St Kilda.

"They have to get out there on the Monday morning and say either, 'He will continue to coach next year, we will honour his contract,' or, 'We are in the market for a new coach.' We will know in a week's time," he said.

"They have to have made up their mind which way they’re going, so in fairness to everyone, announce it to the world a week from now."

Allowing Ratten to coach out his contract would also open up the coaching pool to potentially include Sydney Swans premiership coach Paul Roos, Walls said.

"Paul Roos won't coach next year - (he has) categorically stated that. Beyond that, I think he would be available to coach.

"So you open up the pool in 12 months' time to Malthouse, to Roos, (and) you look at the terrific assistants like Scott Burns, who's done everything right over there with West Coast."