Second-placed Giacomo is unlikely to catch Sydney to Hobart leader Perpetual Loyal but is still due to smash the current race record set by a much larger supermaxi.
The Volvo 70 owned by New Zealand wine industry leader Jim Delegat is making more than 18 knots down the east coastof Tasmania, some 18 nautical miles behind the leader.
"The boat really likes this angle and we're pushing hard and we're going very well, it's very suitable for us," the boat's sailing master Steve Cotton said by satellite phone.
Giacomo's line honours hopes were given a boost with the retirement yesterday morning of leader and current record holder Wild Oats XI, due to hydraulic issues impacting operation of the keel.
Race spokesman Bruce Montgomery said Wild Oats XI was unable to move its keel after a hydraulic ram broke.
However the NZ boat is firming as an early leader in the handicap honours.
"We've got an ETA to Tasman Island of 2am [today] but of course we would really slow up in the Derwent River so it could be something like 5am," Cotton said of his prediction for reaching the finish line.
"The weather will hold but obviously as we approach Tasmania there'll be different circumstances that we may not know about but at the moment we're doing well, we're placed very well."
The leading boat must reach the finish line before 9.23am (NZ time) today to beat the race record of one day, 18 hours, 23 minutes and 12 seconds set by Wild Oats in 2012.
Giacomo is leading a tight pack, eight nautical miles ahead of class equal Maserati, 10 miles ahead of supermaxi Scallywag and 28 miles ahead of fellow NZ entry Beau Geste.
Giacomo last contested the race in 2014, when she was dismasted off the Tasmanian coast, and was sixth over the line in 2013.
