The all-rounder has a batting average of 26 and just 35 wickets from 30 tests but not only will he almost certainly play the first test against India at Adelaide Oval on Thursday, he will take the field as vice-captain of the side.
Former test paceman Geoff Lawson was the first high profile figure to launch a broadside at his selection over the weekend but there will be many more if the ebullient 27-year-old fails to fire against the tourists.
Against Pakistan in October, Marsh managed 30 runs from four innings with the bat and two wickets at the cost of almost 100 runs with the ball and he knows he needs to produce against India.
"I'm just really excited, really pumped for the test summer to start," he told reporters at Adelaide Oval on Tuesday.
"After the UAE, there's a few question marks over me (but) I'm just really pumped, if I'm selected, to get out there and play in front of the Australian crowds again.
"I'm doing my best to make the number six spot my own, that's all I can do."
The number of times Marsh used the word "pumped" in a short news conference might be an indication of why he was given the test vice captaincy despite not being an automatic selection.
Marsh is clearly one of life's enthusiasts, as his summation of Australia's full-on training sessions on Monday and Tuesday amply illustrated.
"It's been unbelievable, hasn't it? I don't know what it's been like to watch but to be part of it has been unbelievable," he gushed.
"We've got a great feeling in this group... we've all trained exceptionally well. We've prepared as best we possibly
can."
Marsh's older brother Shaun is also an almost certain starter despite his even more paltry return of 14 runs from four innings against Pakistan.
The 35-year-old's frequent recalls to the test side have likewise strained the credulity of cricket fans to the point that some have joked the Marsh family must have some kind of hold over the selectors.
Of course, the brothers can point to the torrent of runs they produced in last year's Ashes sweep of England, and Mitchell on Tuesday came out with a defence of his brother that might have served for them both.
"He's always got his knockers, but hopefully people respect him for the fact that he keeps coming back, he keeps working hard and hopefully he'll keep proving some people wrong," he said.
(Reporting by Nick Mulvenney, Editing by Peter Rutherford)
