Gai Waterhouse gets it right more often than not, and her prediction that juvenile Straight Charge would romp home with the opening race at Randwick has proven to be on the money.

The $1.60 favourite was in a class of his own, dictating from the outset and extending his advantage in the straight to post a decisive 3-1/2 length win over Erno's Cube ($6.50) with Pisces ($6) another half-length away third.

Winning jockey Tim Clark said Waterhouse's words were ringing in his ears as he cruised to the line on the Magic Millions-bound colt.

"Gai said when I rang her this morning, 'he won't win, he'll annihilate them' and she was pretty spot-on," Clark said.

"You can often see them trial well then sometimes get to the races and not produce it, but he was really good there. He showed that brilliant speed that he's got and he was able to quicken off that.

"Although he'd had the two strong trials, he will still take a bit of improvement off today."

Straight Charge is in his second racing preparation having finished runner-up to stablemate Espionage in the Breeders' Plate in September.

His performance in Saturday's Drinkwise Plate (1100m) at Randwick has reaffirmed his credentials for next month's $3 million Magic Millions 2YO Classic (1200m) at the Gold Coast, for which he is among the leading fancies.

"He (Straight Charge) has always been a horse who has taken everything in his stride. They're the sort of horses that get to those early races and can handle the occasion," Clark said.

"He has developed a bit in his break and all systems go now to the Magic Millions."

Straight Charge, a son of Widden Stud stallion Written By, was a $270,000 yearling purchase for Yulong Investments.