The passage through the Malacca Strait could take up to three days to sail. Teams must keep a constant watch for commercial shipping, fishing boats and nets and objects floating just below the surface.
And with light winds expected and strong tidal currents, there is a prospect competitors will have to anchor to avoid being carried in the wrong direction.
The team emerging from the strait first will hold a commanding position for the final part of the leg through the South China Sea to Sanya, China. The first boat is expected to finish around February 5 or 6.
The boats failed to lay the point around the top of Indonesia and a close-quarters in-shore tacking duel followed.
Telefonica and Camper traded tack after tack on the 25 nautical mile beat to Pulau We, with Puma not far behind. Telefonica held off the sustained attacks and managed to cling to their lead, but there was only 0.1 of a nautical mile difference as they entered the strait.
"You could have thrown a blanket over the three of us as we crossed the longitude of Palau We," Oxley said
As the leading pack began to round the island, Puma grabbed Camper's second place when they cut the corner as Camper went further off-shore in search of better winds. But when the boats crossed again a few minutes later, Camper had reclaimed second place. They then edged ahead but the cat-and-mouse racing is likely to continue for a few days.