Confined to a hotel room, Marinovic stayed as active as possible using some weights supplied by the club.
"I put in a lot of work and was busy every single day, so I don't think there's going to be a huge catch-up," he said.
"Obviously the footballing side is going to take a little bit (of time), but I'm hoping that after a week or two I'm back up to speed."
After his release earlier this week, the All Whites custodian linked up with his teammates in Wollongong, 90km south of Sydney where they'll be based for some - and probably all - of the upcoming season.
The first members of the squad and coaching staff have been there since early November with Marinovic and Mexican attacker Ulises Davila the latest to assemble. The only player yet to arrive is new marquee signing Israeli striker Tomer Hemed, who landed in Sydney on Monday and is due for release from quarantine on December 14. The new A-League season begins just after Christmas.
Marinovic was a stand-out for Wellington in his maiden A-League campaign, producing a series of commanding performances as the side achieved its highest ever regular season finish of third.
But he returns to a side shorn of two of its standout defenders with captain Steven Taylor now playing for Odisha FC in India and Libby Cacace snapped up by Belgian side St. Truiden. Taylor's central defensive partner Luke Devere is back for another season, with Te Atawhai Hudson-Wihongi and new signing, Australian Josh Laws vying to fill Taylor's role. Young kiwi James McGarry looks the obvious replacement for Cacace, although Academy product Sam Sutton has also been training in that role.
"Once I've had a couple of weeks and a few training sessions watching them play I'll be able to assess them a bit better," said Marinovic.
"But I believe in what the coach has done and I'm sure he's brought in suitable replacements. We'll see how that goes over the coming weeks."
The Phoenix open the new season away at Brisbane Roar on December 29, before a first "home" game at WIN Stadium against defending champions Sydney FC on January 2.