Triple Group One winner Happy Clapper has had a pipe-opener in a Randwick barrier trial when fourth in a heat won by the John Thompson-trained Sweet Deal.

Happy Clapper worked to the line in the 900m-heat on the course proper on Thursday, pleasing trainer Pat Webster with his effort and his recovery.

The Thompson-trained multiple Group One placegetter Dreamforce won the first of the two course-proper trials and will be on the same weight-for-age path as Happy Clapper starting with the Apollo Stakes and Chipping Norton.

The Group Two Apollo (1400m) is on February 15 with the Group One Chipping Norton (1600m) two weeks later.

"Happy Clapper will have another trial over 1200 metres on February 6 and then go to the Apollo nine days later," Webster said.

"He will have a much harder trial and that should have him right for the Apollo.

"He only had about three weeks spelling but it is still good to see he is enjoying it.

"It's exciting to think he is coming back."

Dreamforce, runner-up in the Doncaster Mile, beat three-year-old Standout in a heat also featuring Epsom/Golden Eagle winner Kolding who finished well for an eye-catching fifth.

Group Three winner Sweet Deal edged out Prince Fawaz with Lanciato just ahead of Happy Clapper in their heat.

Dual Everest winner Redzel later finished second in a heat over 725m as he gets ready for a first-up tilt at next month's Group One Lightning over the Flemington straight 1000 metres.

Redzel finished a short head second to Redkirk Warrior in the 2018 Lightning.