The Sydney-based Kiwi hoop is the form jockey in Sydney, riding five winners at Warwick Farm on Wednesday, but despite having the choice of a handful of Everest runners, he will ride on Saturday at Caulfield, where his four Group One mounts include the A$2 million Caulfield Guineas favourite Autumn Sun who is now part-owned by Arrowfield Stud after they purchased a 50 per cent share for an undisclosed sum this week.
A winner of four of his five starts, Redoute's Choice colt Autumn Sun won the Gr.1 JJ Atkins (1600m) in Brisbane last winter and added a second Group One scalp in the A$1 million Golden Rose (1400m) at Rosehill last month to be the $1.90 favourite for Saturday's 1600m stallion-making feature.
"He's the most exciting and most expensive colt in Australia. He's already a dual Group One winner and the class act in the race," McDonald said.
"He's got all the right attributes to be the next big thing in Australian racing."
McDonald has a full book of rides at Caulfield and also rides favoured runners Smart Melody in the Gr.1 Thousand Guineas (1600m), Hartnell in the Gr.1 Toorak Handicap (1600m) and D'Argento in the Gr.1 Caulfield Stakes (2000m).
"It's a big day coming up with those four Group One rides that are all well in the market," McDonald said.
"I had a few to pick from in the Everest but I thought I was better off going to Caulfield and it probably couldn't have worked out any better. These are time-honoured Group One races. It would be great to win the Everest but it would be great to win a Caulfield Guineas too. I'm looking forward to the day."
McDonald won the 2014 Caulfield Guineas on Shooting To Win and was at Caulfield on Tuesday to ride the Chris Waller-trained Autumn Sun as he bids for a second win in the race.
"He cornered like a dream. I don't think there will be any excuses for him. There were a few doubts that he would get around Caulfield because he's such a big-striding horse but from what I felt, he's pretty spot on," McDonald said.
"Barrier five is a beautiful draw for him, though I wouldn't have been bothered if he'd drawn wider out. Because he's such a big-striding horse, I don't really care where I am in running as long as he's got galloping room."
McDonald was excited about the prospects of Smart Melody in the Thousand Guineas and had no concerns about the filly running out a strong 1600m.
"She'll run the mile on her ear," he said.
"It looks a nice race for her. She's so adaptable. She can race on the speed and she's got a turn of foot. I'm pretty excited to be partnering her in that."
After his five winners at Warwick Farm on Wednesday - his third bag of five in Sydney - McDonald has 28 metropolitan wins this season, opening up a lead of eight on arch-rival Hugh Bowman.
"It's going pretty well for me. I even got to ride a double for Stephen Marsh at Gosford last week so that just proves it," he quipped.
While riding raceday in Sydney on Wednesday, McDonald has spent most of his week in Victoria, trialling several international Cups contenders in trackwork at Werribee, among them Count Octave, Sound Check and Finche.
He rides the Aidan O'Brien-trained Yucatan in Saturday's Gr.2 Herbert Power Stakes (2400m) and will confirm his ride for Saturday week's A$5 million Caulfield Cup on Sunday.