The quality mare was the only low point for the Grant and Alana Williams camp after Western Empire continued his winning surge in the Group 3 Belmont Sprint (1400m)-albeit narrowly.

The raging favourite gave punters some heart flutters chasing down Searchin' Roc's from the back of the field, but got the job done on the line to score by a half-length.

Western Empire's victory continued his resurgence under the Williams stable and completed the second leg of a Group 3 double after the Northam Stakes (1300m).

Grant Williams said he was looking forward to Western Empire stepping up to the mile of the Hyperion Stakes in a fortnight before the Strickland Stakes (2000m).

Alsephina, a dual black-type winner, was seen as the likely challenger to her stable mate in the Belmont Sprint , but was a late withdrawal after being involved in a float accident.

On the upside for the Williams', it's not career threatening for the five-year-old, but enough to put an end to her current preparation.

"That was a bit of a freak thing, one of the other fillies was in season and went off as we were putting Alsephina on the float," Grant Williams said on Tabradio,

"She took fright and hurt her eye which need some staples.

"But that will finish her campaign now, the injury is not that bad.

"It's hard to get her right and go first up into a mile (Hyperion).

"She hasn't been a hundred per cent this campaign after racing on hard tracks over the carnival.

"Everything happens for a reason and probably it gives us a good excuse to put her back in the paddock.

"I'm definitely keen on taking her to some of those mare races for the spring (Melbourne) and the wet tracks will suit her.

"We'll stop on her now and she'll get a decent break before setting her for something over east."

The Group 3 La Trice (1800m) and Listed Starstruck Classic (1600m) are valuable additions to Alsephina's racing cv, two of nine wins from her 15 starts to date.

Last time she campaigned she ran seconds in the Group 1 Railway Stakes (1600m), Group 3 Peters Stakes (1500m) and Group 3 Asian Beau Stakes (1400m).

Meanwhile, the bubble burst for Keshi Boom, the filly suffered her first defeat, but Williams was pleased with her first-up performance when running on for 6th.

"It wasn't the ideal run we wanted for her first up, she was never on the track," Williams said.

"But, she came through it really good and this morning she's bouncing around the yard and looks really good.

"She'll head into that three-year-old series now in three weeks."