John Size will have all of his BMW Hong Kong Derby firepower on show this Sunday, even if they are at different points in their run to the classic.

Size sends out Contentment and Thunder Fantasy in the Hong Kong Classic Cup, while Luger finally makes his return to racing with his first attempt beyond 1,400m in the Class Two.

"There are no surprises to them - they're quite exposed already," said Size. "Everyone has seen enough of them to know what they're about."

Luger might have been expected to be one of the season's real stars by now, having earlier won five of his seven starts.

But an irregular heart rhythm at his only run in November and then a fever in late December set him back.

"Nothing's perfect about his preparation for the Derby because he's had those interruptions, and every interruption is significant, but I'm optimistic," Size said.

"He has been ready to race for a while before this weekend, he just hasn't gone to the races. This looks a suitable race to run him and, because it's his first run at the mile, he should be able to improve on whatever he does on Sunday.

"Beyond that, I'll see what Luger's telling me with his race performances and training as to where he goes next."

Luger was already rated high enough to make the Derby field so his seven-times champion trainer did not have to take a path not of his choosing in order to qualify him for the Group One on March 15.

That was not the case with Contentment who is one of the most exciting horses around with three wins in four starts.

He takes his place in the Classic Cup at level weights against much higher-rated opposition, including stablemate Thunder Fantasy, where a good performance would lift his rating to seal inclusion in the main event.

"It's his first run at 1,800m but he travels quite kindly in his races and everything about him since he started has suggested he is up to the quality," Size said.

"And he's versatile - and that's good to know going into Group One races where things don't always go to plan.

"Thunder Fantasy is pretty straightforward, ran a decent race in the Classic Mile when he had a wide run but I'm hoping that he's going to improve as he gets up in distance, too."