The veteran Australian rider was originally diagnosed with a cyst in his neck at a routine medical check-up for his permit renewal back in January, but further scans later revealed something more sinister: He also had thyroid cancer.
Powell, 50, wanted to get treatment back in Australia, but by then, the borders had closed because of COVID-19.
He eventually managed to fly to Sydney on June 28, and after a battery of tests, underwent surgery at the end of July. To his relief, the cancerous cells had luckily not spread to other organs and were removed, while the cyst proved to be benign.
After a few weeks of convalescence in hospital and his relatives' place in Sydney, Powell returned to Singapore two weeks ago, just coming out of quarantine on Saturday.
Now that the harrowing experience is behind him, he just wants to get back in the saddle.
"It's been a very rough road. What started as a normal medical test turned into a nightmare," said Powell.
"COVID-19 didn't help matters as it held me up when all I wanted was to treat it as quickly as possible. The tests, the surgery, the biopsies and the waiting were not easy, but thank goodness, it's all behind me now.
"In Australia, I was able to see my daughter Madison for a few days before the surgery, but because she's in a hot spot in Queensland and the border restrictions, I couldn't see her afterwards. It's hard, mate.
"But I've got to move on. I've already spoken to the chief steward Terry Bailey and I should be good to start riding trackwork again fairly soon.
"I'm looking at a comeback on Singapore Guineas day on September 26. We'll see, but in any case, I won't be taking too many rides for a start, just take my time to get back into full fitness."
Despite his limited opportunities as a heavyweight jockey, Powell was enjoying one of his best seasons at Kranji before COVID-19 came about. He was even joint-second with Ruan Maia on 15 winners at the end of March, but has now slipped down to ninth place.
The dual Singapore Derby-winning jockey (Hello And Goodbye in 2005 and Clint in 2011) rode his last winner Lim's Spin for Stephen Gray on March 20.
"I've been keeping an eye on what's happening at Kranji. Pity the crowds are not back, but at least, we are still racing," he said.
"It'll be great to see all the mates again, but above all, I can't wait to get back to riding again."