Not even Master Lock Comanche's skippers could have predicted preparations would go so well for her Sydney to Hobart revenge.

Under new skippers Matt Allen and James Mayo, the 100ft super maxi took line honours in Tuesday's Big Boat Challenge on Sydney Harbour after leading throughout the two laps from Point Piper to Manly.

Comanche crossed the finish line off Fort Denison 55 minutes, 16 seconds after the starting gun but only 54 seconds before second-placed LawConnect, which upset Comanche to finish last year's Hobart first.

Mini-maxi Whisper was declared winner on handicap before URM Group was disqualified for failing to give way to Wild Oats X, which lodged a protest.

The protest committee found URM could have avoided contacting Wild Oats' GPS antenna with its spinnaker halyard.

Comanche's latest win comes after the boat often rated the world's most powerful 100ft yacht took both line and handicap honours in the Cabbage Tree Island Race at the weekend.

Her quest to bounce back from Hobart disappointment also included a line honours win at the Tollgate Islands race from Sydney Harbour to Batemans Bay and back in October.

"The lead-up has been great," Allen said.

"We planned this run-in a long time ago. The results have been probably than we ever hoped.

"This is like the home- and-away season, the grand final's coming up. It's not far away and this is the last time we're going to have all the crew together today until we get together on Boxing Day."

Former Australian Sailing president Allen and hardware tycoon Mayo only took charge of Comanche this year, but have had the 2023 Hobart at the front of their minds since.

LawConnect ambushed Comanche in the River Derwent last year, crossing the line 51 seconds ahead of the runaway favourite.

"That hurts. There are no prizes for second. This (year) is about a bit of redemption," Mayo said.

"We've just got to try and keep the momentum going. There's a long way to go."

Comanche was fastest out of the gate on Tuesday, leaving the spectator fleet behind as she clocked 27 knots in a southerly to Manly.

She endured a stiff early challenge from Wild Thing 100, another 100ft supermaxi at much longer odds for Hobart line honours.

But Wild Thing fell behind on the first upwind stretch to Shark Island, and eventually finished third on line honours after a race in two emerged between Comanche and LawConnect.

LawConnect sailing master Tony Mutter remained confident in his boat's Hobart chances despite Comanche's recent run of form.

"We've got a lot of positives. We stayed pretty close to them today, we actually got pretty close to them up the beat halfway through that race, just after mark one," he said.

"(Has it affected the) confidence? I don't think so, (Comanche) are more of a known quantity."

Comanche will return to the water on Wednesday to host a group of Allen and Mayo's friends, including Australian Olympic cycling champion Anna Meares.

Vice-President of the Australian Olympic Committee, Allen was part of the team that appointed Meares as Chef De Mission for the Paris and Los Angeles Games.

"She did a great job for us in Paris and sailing's an Olympic sport, albeit in slightly different equipment than Master Lock Comanche," Allen said.