Lyle, 35, has twice beaten cancer: as a 17-year-old, when he was initially diagnosed with acute myeloid leukaemia, and after a relapse in 2012.

The Victorian is reported to be at Royal Melbourne Hospital, as doctors conduct tests. He will take a break from golf.

"Just another bump in my road. I will fight like no other," he told PGATOUR.com.

A family spokesperson told Golf Australia: "A routine blood test conducted earlier this week returned abnormal results and Jarrod was immediately admitted to hospital and placed under the care of his previous medical specialist. He will remain there at least until a full diagnosis has been made.

"He has undergone several tests, and will have several more in the coming days. At this point, we have not yet received complete test results, so there is no definitive diagnosis and we do not have an agreed treatment plan.

"We cannot speculate about anything until we get more information. We are grateful to be surrounded by incredibly supportive people and we truly appreciate your consideration and respect for our privacy at this time." 

n his first tournament back from beating cancer a second time, at the Australian Masters in 2013, Lyle reflected on his battle. 

Lyle had to wipe tears from his eyes before and after his opening drive at the tournament, admitting afterwards that giving his young daughter a kiss and seeing her "go daddy" T-shirt was "the end of me" from an emotional standpoint.

"I just sort of stood there and thought, you know what? Twelve months ago at this exact tournament I was saying 'I do not know if I will ever be playing golf again'," Lyle said.

"To stand up on that first tee and to hit it and see what has happened over the last 20 months of my life, and my wife's life, and my daughter's life, everything was there."

Lyle's second battle with cancer occurred at the same time as the birth of his first daughter, Lusi. He and his wife Briony welcomed a second daughter, Jemma, last year.

He returned to the US PGA Tour in 2015, using his medical exemption in an attempt to win back a tour card.