At 36, the impish attacker might be forgiven for viewing his one-year deal back in his home city as the final chapter.
But after netting 55 goals in 88 games for Celtic to guarantee legendary status at Parkhead and seven in 13 in helping save Patrick Thistle from dropping out of the Scottish Championship last season, McDonald isn’t calling time on his career just yet.
With his football mortality on hold, McDonald said: “I’m not thinking that I’m here for a last hurrah - if I thought that way I’d be defeated already.
“It all depends on how I go. I’ve got to be honest with myself and the club will be as well.
“But If I can add value beyond this season, whether that’s on all of the pitch, then time will tell.”
Western United are shaping as the beneficiaries as McDonald eyes what he views “as a risk worth taking”.
“I’ve wanted to come home for a while now and it’s a great opportunity to challenge myself in a different environment after so many years away,” said McDonald.
“I’ve pretty much done everything I can, or have ever I wanted to do, in the UK and in Scotland in particular.
“At the beginning of last year there wasn’t much more to go for and I went down a different route into the media side of things (with the BBC) and was really enjoying it.”
Fate intervened in a plea from Patrick, and true to form and reputation McDonald delivered as he has done for most of his career during spells at Southampton, Celtic, Middlesbrough, Millwall, Motherwell and Dundee United.
“Coming home was an opportunity too good to turn down,” he added in reference to Western’s football director Lou Sticca reaching out to him.
“I wasn’t able to get here before now but everything happens for a reason and I’ve finally made it back.
“I plan to perform and do well which I still think is in me. I’ve looked after myself really well in the last six or seven years in terms of changing my body shape and fitness levels. That’s why am still able to go.
“It’s a great opportunity to start afresh with a great bunch of boys and a brand new club. It’s exciting.”
With 203 career goals - though none for Australia in his 26 appearances- McDonald knows the expectations will be high - even though he’s into added time at the end of his career.
“Hopefully I can cause a few surprises but more importantly hopefully we as a team can spring a few surprises.
That’s what I want more than anything. The team to be successful.
“This isn’t about me coming home and doing everything for myself ... it’s about me bringing my experience to help the manager and help the players to build something special.
“I really believe the squad we put together is one that is going to seriously challenge the season.
“It’s early days and it may take time. It may not all be beautiful, great and amazing at the beginning but we’re looking to build and I’m sure we’ll be there or thereabouts come the business end of the season.”
McDonald plans to ultimately transition into coaching and sees many virtues in Mark Rudan whom he believes will drive the club forward, beginning with their season-opener at former side Wellington Phoenix on October 13.
“Mark’s ideas are something I’ve bought into. He loves to play attacking football and that’s great for me,” added McDonald.
“He’s a ballsy coach who isn’t afraid to go after things. He’s always on the front foot and likes his teams to play that way, as you saw with Wellington.
“We need to get people excited about this club and there’s no better way to do that than by producing performances.”
After regulation wins over local opposition, the degree of difficulty rises in the weeks ahead with looming warmups, beginning behind closed doors against Victorian rivals Melbourne City on Tuesday.
Adelaide United and Sydney FC have also been locked in.
“These games will show where we’re at and what the manager wants,” said McDonald.