Australia's opening batsman Aaron Finch has rarely felt more pain on the cricket field than in the moments after his battered right index finger was jammed by Mohammed Shami in Perth, to the point that it felt like the digit was "going to explode" from a blow that left bone visible from a deep cut.

However, Finch is adamant he will be fit to play on Boxing Day for his first Test in front of an MCG home crowd, for what looms as the pivotal match of the entire Border-Gavaskar series.

Given the captain Tim Paine's lengthy history of breaks, surgeries and problems with his right index finger, Finch's own saga of finger troubles seems minor, but is typical of the many issues that batsmen tend to have to manage over the course of summers and careers. He first broke it in Sri Lanka in 2016, and this summer had it twice struck by Mitchell Starc in the nets in Perth and Adelaide before Shami dealt the most painful blow during the second Test, forcing Finch to retire hurt.

"It was a bit of a shock, just the initial pain was the thing that got me. It felt like it was going to explode, which was quite funny," Finch said in Melbourne. "I think just being hit a few times in the last month, a couple times by Starcy at training then Shami out in the game, but it's also an old break.

"I broke the same finger in Sri Lanka a couple of years ago, so I've got to start either catching them or use my bat instead of my gloves. It was up there [as the most painful]. I think snapping my hamstring tendon [in April 2015] was probably the most over the last few years."

For all of Finch's considerable discomfort and the disruption to Australia's batting order, he was able to feel considerable improvement even within the Perth Test, though he did not really get much opportunity to assess his own batting after falling first ball, glancing down the leg side into Rishabh Pant's gloves, when he resumed his second innings.

"Even batting in the warm-up before the second innings in Perth I still felt pretty good. Catching might be a bit of a different issue, at training I always tape my finger up anyway, but this'll just be a bit of extra padding," Finch said. "With a Boxing Day Test and being from Victoria it's going to have to be cut off I think.

"I'm going to catch in slips at training and do my normal preparation. If anything changes in the next couple days I'm sure we'll have to sit down and chat about that, but at this stage it's still business as usual and I plan to field at slip and whatever else is needed. It feels like it's improved 100% over the last couple of days."

Asked whether Paine had any advice in the area of managing a problematic finger, Finch remarked admiringly of the captain's ability to withstand obvious discomfort. "He's got about 15 screws and a couple metal plates in his so a little bit different, he's carried that for a lot longer than what I have," Finch said. "He's got a high pain threshold."

At the end of a year in which he has gone from being a white ball-only cricketer for Australia to now having a critical role in the Test team and a vastly expanded international workload, Finch was happy to have spent several days at home after Perth - even if he and his wife Amy used the rare time in Melbourne to move house.

"I do feel refreshed, but at the same time I had to move house during that period so my wife had to do a bit of extra heavy lifting which is unfortunate for her, but it's just great to be home," Finch said. "Whether going for a coffee at the local cafe or going out for breakfast or lunch or whatever it is, just a bit of familiarity with being home is always nice."

Nevertheless, Finch did find time to grip a cricket bat in between national team duties, giving him some sense of how the finger may feel on Boxing Day. "I got sent some new bats," he said, "so I've been walking around the loungeroom waving them around and it feels okay."