Sinisa Mihajlovic is facing a new leukaemia battle after the Bologna head coach revealed he is heading back to hospital for treatment.

The Serie A stalwart, who played for Roma, Sampdoria, Lazio and Inter, was first diagnosed with the disease ahead of the 2019-20 season and underwent a bone marrow transplant in October 2019. He was back in the dugout six weeks later.

He has remained boss of Bologna since then but will step away from his responsibilities for an indeterminate period after revealing he has encountered a setback.

Mihajlovic announced the news on Saturday, telling reporters in a news conference that a routine test had given cause for concern.

"In recent years the recovery was excellent, but unfortunately, from the latest analysis some alarm bells have emerged and there is a risk of a reappearance of the disease," Mihajlovic said.

"This disease is very courageous in returning to face an opponent like me."

Former Yugoslavia hard man Mihajlovic, who has coached teams including Sampdoria, Milan and Fiorentina, spoke of the challenges of always knowing there might be a bump in the road after his initial recovery.

"You can fall, and you have to find the strength to get up," he said. "At the beginning of next week I will have to be absent, and I will be hospitalised again at Sant'Orsola. I know I am in excellent hands. Unlike two and a half years ago, when I was in tears, this time you see me calmer.

"I know what I have to do, and my situation is very different than it was then."

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Mihajlovic is hoping for a swift return to his Bologna duties, but it will not be immediate. "I will certainly have to skip some matches," he said.

Bologna sit 12th in Serie A and have won just one of 10 league games since the turn of the year, losing six times. Mihajlovic is convinced his players can thrive without him and rise to his encouragement which will come from afar.

Their next match is an April 4 clash with leaders Milan.

"I know they will fight for me. They are all good guys and good players," said 53-year-old Mihajlovic. "I ask the wonderful Bologna fans to support and help them, I am sure it will happen both in training and in matches.

"None of us will give an inch, we'll move up in the table, and I'll be back with the team soon."