Miami - American skipper Ken Read threw the Volvo Ocean Race wide open on Wednesday after guiding his boat PUMA to a second successive stage victory while the overall leaders laboured behind in fourth.
Read continued the form which earned his US-led boat victory in the treacherous fifth leg through the Southern Ocean with a win in the 4 800-nautical mile sixth stage from Itajai in Brazil to Miami.
With Spanish pace-setters Telefonica struggling to rediscover the pace which earned them three straight leg wins after the race began in Alicante, Spain, the 50-year-old Read could yet snatch ocean sailing's most prestigious trophy. He was runner-up in 2008-09.
PUMA took their overall points tally to 147, two behind Iker Martinez's crew although the Spaniards will pick up 15 points if they finish fourth as predicted later on Wednesday.
Camper (Spain/New Zealand) were heading for second place with France's Groupama in third and Abu Dhabi trailing the rest of the fleet in fifth.
"This is unbelievable," Read said after crossing the line in the company of about 100 spectator boats.
"It's great to be back in the United States. Actually we've been to Miami before in this boat, so this marks our complete circumnavigation.
"It was touch and go, the guys on Camper sailed very well, but I couldn't be more proud of our team, they did an unbelievably great job."
The 39 000-nautical mile race crosses the Atlantic to Lisbon, Portugal for the seventh leg, before sailing to Lorient, France and then finally Galway, Ireland in early July.
Each leg win is worth 30 points to the winners.