The rucial Matildas midfielder is eager to roll up her sleeves to help Australia out of its self-dug World Cup hole.

She's declared herself fit and ready to start in Friday morning's (AEST) clash with Brazil, a crucial match after Australia's first-up 2-1 loss to Italy.

Kellond-Knight's return would add much-needed composure in midfield.

In another boost for the Matildas, Mary Fowler will also resume full training on Tuesday in Montpellier, the site of their match with Brazil, as the 16-year-old bids to make a World Cup debut.

Kellond-Knight carried a hamstring injury into the Matildas' pre-tournament training camp and suffered a calf issue once fit.

That restricted her to just 10 minutes against the Italians, but the 28-year-old now has her hand in the air for selection.

"I feel great now, I'm ready to go," she said. "I would have played 90 if I was allowed, it's just the medical staff holding me back."

Kellond-Knight admitted frustration in the Matildas dressing room after the loss, but the team had already put their negative views behind them.

"We deserved more than a loss out of it ... but I'm an experienced player and I know the whole tournament doesn't depend on the first game," she said.

"Spain lost their first game years ago in the (2010) World Cup and came through and ended up winning the championship."

So, how can Australia improve?

Kellond-Knight believes there will be immediate improvement from knowing their opponent.

Australia have faced Brazil seven times in the past four years, including their historic 1-0 win at the last World Cup that secured the Matildas a quarter final place.

The 28-year-old admitted a renewed focus on defensive duties would be needed, but rejected the notion that the transition from former coach Alen Stajcic to Ante Milicic could be to blame.

"Even Staj encouraged us to play out from the back and it's the way we want to play," she said.

"We want to be proud of building up from the goalkeeper to creating chances and we're never going to shy away from that, I think it's kind of ingrained in the Australian philosophy.

"You see the men do it and we're going to do it. We're never gonna turn into a direct team.

"We're going to band together as a team and listen to what the coaches have in terms of feedback and how we can tighten that up."