Melbourne, Dec 26 (IANS): Former Australian all-rounder Tom Moody, the man who transformed Shaun Marsh's career, feels that the young batsman's biggest challenge after giving up part lifestyle is his fitness.

Marsh, who fell for a duck during Australia's first innings in the Boxing Day Test, was struggling to get fit in time for the Test due to his recurring lower back problem.

"I don't think the issue is him playing consistent cricket; it's about the consistency of him staying on the park. That's his greatest challenge. It's a tricky one for Shaun because he's clearly fit and as much an athlete as any other member in that squad, but he's got an issue with his lower back," said Moody.

Marsh made 81, 18, 44 and 0 in his four subsequent Test innings against Sri Lanka and then South Africa - averaging 56.8 after three Tests - before breaking down in Cape Town last month.

Moody, who was instrumental in shaping Marsh's career while being a Western Australia coach, said handling the back injury is his biggest challenge if he wants to prolong his career.

"Without being a physio, I don't know but I imagine there's got to be some sort of relationship between that and the hamstring injuries he's had over the last couple of years," Moody was quoted as saying by The Sydney Morning Herald.

Moody is confident that once Marsh is injury free, he won't look back in his career.

"The challenge he has is getting opportunities on the park regularly to show his consistency with the willow in his hand. Once he is injury free, I don't have any doubt whatsoever that he won't look back with regards to his form in the middle," he said.