Water Police are battling rough seas to rescue a sailor injured when a charity boat rolled in Bass Strait.

The three-person crew had planned to row from Wilsons Promontory to Tasmania as part of the George Bass Expedition, and set out on Saturday.

But three days into the journey poor weather saw their effort come to a sudden end off Victoria's coastline with crew member, 27-year-old Ben Turner, breaking his elbow.

"Just capsized," the skipper Margaret Bowling wrote on Twitter.

"All 3 of us were in cabin and boat righted FAST."

Emergency crews were called about six hours later on Tuesday morning to rescue the crew of the 24-foot boat.

Water Police are facing two to three metre waves and 40 knot winds to rescue the injured sailor, and they're not expected to reach the trio until about 8pm tonight.

Acting Sergeant Nathan Gardener said the crew will attempt to row towards Deal Island with injured Ben onboard.

He said the trio are in good spirits despite their ordeal and officers remain in communication with them.

Ben and two other crew members were completing the run to Hobart in a warm up event for a bid to row from Peru to Sydney, starting in April.

He is out to raise money and awareness for cystic fibrosis and won't be deterred by the accident.

When the police launch, Fearless, reaches the injured rower, a decision will then be made whether to take him to a nearby island or bring him back to the mainland.