Harris hasn't played Test cricket since the 2019 Ashes where he made just 58 runs in six innings. Stuart Broad and Jofra Archer dismissed Harris five times between them, all from around the wicket and all where he was squared up.
Harris identified that he needed to make a technical adjustment but found it difficult to do last season with less than a month between the Ashes and the start of the domestic summer.
"Pretty much since the end of the Ashes almost I've been trying to work on how I can stay a little bit more side-on and some stuff like that," Harris told ESPNcricinfo. "It was hard to try and work at it in season, so I never did much of it during the season."
Harris did score a century in his first Shield innings last summer but it came on a lifeless Junction Oval pitch where six players reached triple figures, two of which were double centuries, and only 12 wickets fell in four days.
He made four more half-centuries for the summer in 10 innings but none exceeded 70. He missed out in the tour match against Pakistan in Perth and lost his Test spot to Joe Burns.
Harris was keen to work on getting more side-on in his set-up and strokeplay over the winter but coaching changes in Victoria and the Covid-related state lockdown provided some hurdles.
Harris' long-time batting mentor Lachlan Stevens moved from the Victorian men's program to the women's program while and one of Harris' other sounding boards, Andrew McDonald had left Victoria's senior coaching role early last summer to join the Australian team as an assistant coach.
Victoria were without a senior coach right up until mid-August when former Victoria and Australia opener Rogers was appointed. Harris worked diligently with Victoria assistant coach Andre Borovec in the interim.
Under the McDonald, Stevens, Borovec and Mick Lewis coaching unit Victoria's batsmen in particular had been given the freedom to explore their own technical preparation within reason, with the coaches fully supporting and working with the player-made plans and only intervening when form issues demanded it.
Rogers has a different philosophy having come from coaching Australia's Under-19 team.
"He's very different to [McDonald]," Harris said. "He's very technical and he likes tweaking. He's very focused on that sort of stuff. Which is not wrong or right, every coach is different. He's been good.
"He has just helped me a little bit with my alignment and just getting myself in a better position. That's been really good. I just work with whoever. All our staff are all very helpful."
Rogers stated when he got the job that developing Victoria's young batsmen into long-term Test players was his top priority and he specifically mentioned that he had "some ideas about how Marcus can go about it."
The pair have worked very closely together during the 14-day quarantine period Victoria had to undergo in Adelaide ahead of their Sheffield Shield return. They could only train in groups of four under South Australia's government guidelines that changed just prior to Victoria arriving in Adelaide, and it forced Cricket Australia to reschedule the Shield fixtures as a result.
"Buck [Rogers] was in my group of four so it was good to spend some time with him and just work out how he goes about it with his coaching," Harris said. "He asks a lot of questions just to see what response he gets out of people.
"You could have a group in the gym, a group in the outdoor nets, and a group on the outfield, but you couldn't all be in the same place at once. So it was pretty hard. It didn't make much sense. You'd all come to ground on a bus but then you weren't allowed in the same place outdoors. But the rules are what they are."
While Harris enjoyed the technical coaching, he wasn't sold on Rogers' taste in music. "In the two weeks that we had in the nets he had his disco music on every day so if that means anything I don't know," he said. "I haven't had any coaches who have listened to that stuff."
With CA rejigging the schedule Victoria had nine days out of quarantine before starting their Shield season against South Australia at Glenelg on Friday. South Australia, Tasmania, and Western Australia have each played two matches already while Queensland and New South Wales have both played one.
Victoria held a centre-wicket practice at Adelaide Oval No.2 last Saturday where Harris was able to implement his new set-up.
"It feels good," he said. "I started working on it six weeks ago and for the first little bit it felt uncomfortable, but then we had a good centre-wicket on Saturday on a wicket that was doing plenty and I think I batted for 30-odd overs and got retired. It was good in those two weeks to put some work in and be able to knuckle down a bit."
As for his Test aspirations, Harris is crystal clear on where he sits in the pecking order after discussions with national coach Justin Langer and Rogers, among many others.
"There's just a few things that I need to tweak a bit and also I know that it's pretty simple," Harris said. "If I just make runs that will put me in a position to at least be spoken about and if you don't you find yourself not in the side.
"It's pretty easy. I think you've got to be making hundreds and hundreds that people take note of. [Travis Head] made 171 not out and Cam Green got 197 so you've got to do things like that if you want to get back in the side or push your way in. That's what I've got to do but I also know I can do it."
Alex Malcolm is a freelance writer based in Melbourne