A virus has been discovered in reigning Victorian four-year-old trotting entire or gelding of the year Rules Dont Apply following his disappointing return to racing on Saturday night.

Having his first start since February’s Australian Trotting Grand Prix, Anthony Crossland’s top squaregaiter led the Woodlands Stud Trot field at Melton before dropping out sharply to finish second last behind winner Aldebaran Zeus.

Crossland took to Twitter on Tuesday, saying a post-race veterinary examination revealed that the gelding had experienced “the thumps” and that he would undergo further blood tests.

Those checks uncovered a virus, which will see Crossland give the five-year-old a short break to recover.

“He’ll have a week off and then start again,” Crossland said.

“Sometimes preps just go bad and you’ve got to just put them to bed.”

Rules Dont Apply’s last campaign produced a Group 1 victory in the Vicbred Super Series 4YO Trotting Entires and Geldings Final and included a heat success in the Great Southern Star series.

The horse is owned by a large group of connections that features former Geelong footballer and well-known media identity Billy Brownless.

Rules Dont Apply has won nine of 26 career starts for prizemoney up over $140,000.

Crossland told thetrots.com.au before the weekend that it was unlikely he would chase a start in the Inter Dominion Trotting Championship later in the year.

He said the Group 1 Australasian Trotters Championship at Melton on September 10 was a likely early major race for the horse before working towards having another tilt at the Great Southern Star and Australian Trotting Grand Prix in the new season.

It’s unclear how his latest setback will alter those plans.