Line honours in this year's Sydney to Hobart yacht race is shaping as one of the closest battles in the history of the event, with a group of four in the leading pack slowly moving down Tasmania's east coast.

The grudge match between Comanche and Wild Oats XI has been playing out on day two but two other super maxis — Black Jack and InfoTrack — are making it a four-way tussle which could go all the way to Storm Bay.

Key points: Four super maxis are in the battle for lead, with Comanche slightly ahead

Four super maxis are in the battle for lead, with Comanche slightly ahead Winds eased as the leaders powered into Tasmanian waters

Winds eased as the leaders powered into Tasmanian waters Finish time could be as late as midday Friday AEDT

The lead has been changing throughout day two with just 5 nautical miles separating the four yachts as they crossed Bass Strait.

Wild Oats XI is keeping pace with the leaders' pack, after earlier taking a more eastward track but at 7:00pm AEDT, Comanche was holding the lead travelling at just over 15 knots.

By 1am, winds had picked up dramatically with the first yacht projected to arrive at 6:15am.

Comanche maintained the lead, travelling at 13 knots and followed by Black Jack in second and Wild Oats XI in third.

The Moody 54DS Calypso retired from the race late on Thursday night, bringing the fleet to 80 yachts.

'Thriller in slow motion'

Any chance of a race record vanished on day two but race media director Di Pearson said it was one of the event's closest-ever races.

"It's a thriller in slow motion," she said.

"The breeze has dropped out somewhat and Comanche has just a very, very small lead over Black Jack from Queensland," she said.

"Black Jack loves lighter weather so she's right on Comanche's hammer."

Eight-times line honours winner Wild Oats XI is this year aiming to reverse its recent fortunes, after being penalised an hour by race officials for failing to keep clear while tacking during 2017's event, with Comanche sensationally awarded line honours in a record time of one day, nine hours, 15 minutes and 24 seconds.

Seawater washes over InfoTrack as it powers towards Hobart during the 2018 Sydney to Hobart yacht race. ( ROLEX/Studio Borlenghi )

Skipper Mark Richards told yacht race media he could not see foresee a way to get the jump on the others in the leaders pack.

"I think it will go all the way to the finish line," he said.

"It is going to be a very tight race. But we lost about 8 miles [earlier when they were caught on the wrong side of a high pressure ridge] very, very quickly. So that is how quickly it can change."

Cruising Yacht Club of Australia (CYCA) commodore Paul Billingham said it was anyone's race and the four crews were trying to find an edge.

"Three or four miles have separated the entire fleet, one boat gets a mile ahead, then the rest come back," he said.

"I think they are all trying to find that particular advantage, trying to sail to their own particular advantage," he said.

Black Jack is one of the super maxis in contention for line honours. ( AAP: Mick Tsikas )

Wild Oats crew member Chris Links said it was "the closest race we've been in", with Black Jack and InfoTrack adding to the drama.

"We've been in close races with Comanche before, but never been in such a close race with four of us."

Black Jack hoping for a 'shutdown'

Black Jack leads the fleet out of Sydney Harbour on day one. ( Instagram: Official Rolex Sydney Hobart )

Black Jack navigator Tom Addis rated his yacht's chances in the River Derwent finish as "quite good".

"We're really strong in about 8 knots," he said.

"If it is more than 10-12 knots, the more powerful boats go faster but if it's lighter we can go a lot faster than them.

"We're hoping for a shut-down."

InfoTrack, sailing as Perpetual Loyal, won line honours in 2016 and was fourth in 2017 before a penalty relegated it to 24th.

Comanche was in the lead for most of day one. ( Rolex/Studio Borlenghi )

'A cat and mouse game'

Paul Billingham said his "best estimate" would see the super maxis in the River Derwent by lunchtime on Friday.

Once the leaders round the Iron Pot and head into the Derwent, the wind can drop off, leaving crews agonisingly close to the finish line with nothing in the sails.

The race for handicap honours is also close, with Midnight Rambler in the lead.

InfoTrack, formerly Perpetual Loyal, sails out of Sydney Harbour on the first day. ( Instagram: Official Rolex Sydney Hobart )

He said the handicap lead was "changing every five minutes" and described the race between the line honours leaders as a "cat and mouse game".

Tribute to 1998 victims

Celestial was within the top 20 for line honours at midday on day two. ( Instagram: Official Rolex Sydney Hobart )

The light winds in this year's race are a stark contrast to the conditions 20 years ago when six people lost their lives.

A tribute to the sailors was broadcast to participants in this year's event, with words from the 1998 memorial read out during their 5:00pm radio update.

It read:

Mike Bannister, John Dean, Jim Lawler, Glyn Charles, Bruce Guy, Phil Skeggs. May the everlasting voyage you have now embarked on be blessed with calm seas and gentle breezes. May you never have to reef or change a headsail at night. May your bunk be always warm and dry.

Four yachts have been forced to retire so far, taking the fleet of the 628-nautical-mile race down to 81.



Patriot retired at sea with a broken rudder, M3 Team Hungary could not continue after being "dismasted", while Zen's race was ended due to "rig damage".

On its Facebook page, the crew of Scallywag posted they had to pull out "due to the bowsprit breaking off".

"Fortunately, no-one onboard were injured and the team are currently making their way back to shore … the team is deeply saddened," Scallywag's crew wrote.

ABC Hobart will be broadcasting the race finish live on Facebook.

Sorry, this video has expired The leaders in the Sydney to Hobart on day one (Photo: AP. This video has no sound)