Thomson was just 0.65 nautical miles (1.2 kilometers) ahead of Le Cleac'h in Banque Populaire VIII.
Thomson, on Hugo Boss and aiming to become the first non-French winner of the gruelling race, was just 0.65 nautical miles (1.2 kilometers) ahead of Le Cleac'h in Banque Populaire VIII.
But the leading pair, now into the Indian Ocean and heading towards Australia, were more than 660 nautical miles ahead of third place Sebastien Josse on Edmond de Rothschild.
After 25 days, the 29 yachts have been cut to 25 spread over almost 4,850 nautical miles.
Thomson was the early leader but Le Cleac'h overtook five days ago after the right foil on Thomson's vessel was broken by an underwater object.
Josse has said he believes he can still catch the leading pair. But Thomson and Le Cleac'h have set a record-breaking time so far. Le Cleac'h said on Wednesday however "I am not sure I will be able to keep up this pace for the whole race."
The race started in Les Sables d'Olonne on France's west coast on November 6. The winner is expected back in port around January 20.