Sure, Bowman has taken the back end of the season off for some post-Winx rest but McDonald is 40 clear of everybody else, a pack headed by Tommy Berry and Kerrin McEvoy.
Add to that Victorian victories like the Caulfield Guineas on The Autumn Sun and it is easy to forget the 27-year-old was only just returning to the saddle this time last season after 18 months disqualified.
McDonald neither forgets nor dwells on his time on the sidelines.
"Sure, it makes all this more satisfying but I really don't think about it much," he says of his premiership domination.
"I am just loving being back at work and to be honest this season has gone really fast so it hasn't been that tiring.
"Still, I have ridden at a lot of meetings to get to this number but Darren Beadman holds the record at 164 (2007) and I have no idea how he did that."
McDonald is the first rider since Beadman to break the ton, his double yesterday taking him past A$10 million in stakes in Sydney metro races alone.
Tellingly, his two winners yesterday were for trainers Chris Waller and James Cummings, who now rule Sydney racing.
Both men have used McDonald extensively this season and if they continue to do so there may be no stopping the Kiwi.
McDonald's season of excellence will see him return to Hong Kong on Sunday for eight rides, including Glorious Forever in the Champions and Chater Cup.
"It is great to be riding back up there and to have a good book of rides," says McDonald.
"And maybe, if the right offers came, I could see myself living back up there.
"But for now I am very happy in Sydney. It is really cool how things are going here."
While he is off to Hong Kong this weekend, McDonald can't see himself heading to racing's spiritual home Royal Ascot next month, as much as he would love to. McDonald became a rare New Zealand jockey to win at Ascot's Royal meeting when he partnered Expert Eye to win the Jersey Stakes last season and the history, occasion and world class
competition of the magical five days thrill him.
"I love it and I'd love to be going back," he admits. "But I haven't got any bookings yet and I would struggle to go for just one or two. So unless something changes in the next few weeks, sadly I'll miss it."
A silver linings kind of guy, McDonald finds one in missing Ascot.
"Not long after that I am going to take a holiday, a non-riding holiday and a little break from racing.
"It is not that I am not enjoying it because I am loving it but I realise if I don't have a break at some stage I will eventually hit the wall.
"I want to freshen up for the spring and be ready to give that my best. It is a really important time of the year so being mentally fresh for that matters."
But McDonald says regardless of how in demand he is, he still sees himself riding at some key New Zealand meetings next season, like his favourite, Karaka Million night.
"I still want to get home for a few meetings. I love it. It is home."
Magic Mac
• Two wins yesterday extended James McDonald's lead on the Sydney jockey's premiership to 39.
• He is the first rider to win over 100 races there in 12 years.
• McDonald will ride in Hong Kong this Sunday but is likely to miss Royal Ascot, where he rode a winner last season.
