John Sargent isn't ready to abandon his Golden Slipper aspirations with Royal Witness despite the colt's underwhelming debut at Randwick.

Before his first start on Wednesday, the colt was supported from $151 to $26 for the Golden Slipper on March 24 but eased to $51 after his fifth in a Maiden Plate (1000m).

Royal Witness looked well placed on the run home but lost impetus over the closing stages to finish 2-1/4 lengths behind the winner Zousain.

Tye Angland was reprimanded for allowing third-placed Hiemal to shift in on Royal Witness at the 50m mark but Sargent reckoned the damage had already been done to the $2.15 favourite.

"The race didn't go to plan. It was run that fast early that he was out of his comfort zone," Sargent said.

"You could see he was never on the bit travelling. He had his chance but he did have a big blow.

"He'll back-up in a couple of weeks. We've still got a chance if he's good enough to see where we go.

"He'll keep and I'll go to a 1200 in a couple of weeks.

"There's a lot of improvement there. He's a strong colt. He'll back up pretty quick and that'll be the defining moment on whether we carry on to the Slipper."

Upcoming races include a 1200m-race at Canterbury on February 21 or the Silver Slipper three days later.