Charmed Harmony will be given his chance to win a Group One race before he heads for a well-earned spell.

Trainer John Sadler had been considering running him at Caulfield on Saturday but has decided to give him his chance in the Sir Rupert Clarke Stakes (1400m) on September 26.

Charmed Harmony has been in work since the start of the year and while he has been freshened along the way, Sadler says it is time he has a good break.

"The Rupert Clarke will be his swan song," Sadler said. "He's been racing since February."

Sadler said Charmed Harmony's campaign had been filled with highs and lows.

The lows came at the start of his preparation when he finished last at Randwick and was found to have cardiac arrhythmia and then put in a poor showing at Geelong in April.

The highs have been Charmed Harmony's five wins, the last four on end.

"He didn't travel up to Sydney well and I shouldn't have run him," Sadler said.

"He had cardiac arrhythmia and then at Geelong ... I still can't work that out.

"He raced well either side of it but he's got into a zone now and has a lot of confidence."

Charmed Harmony won a 1400m race at Caulfield on August 29, running quicker time than Boban did on the same day to win the Group One Memsie Stakes.

Sadler wanted to run the gelding in the Memsie but he failed to gain a start as an emergency.

"He's probably justified a start in the Rupert Clarke," Sadler said.

"Linton should have won it a couple of years ago when he got trapped deep the whole way.

"I said to (RV handicapper) Greg Carpenter what would be the best race for him during the spring and he said the Rupert Clarke.

"Not that there's any easy Group Ones, but it's the easiest Group One of the spring.