At the midpoint of Saturday’s competition, the Pole, driving a Citroen DS3 RRC, is 1min 38.5sec ahead of Ukrainian Yuriy Protasov in a Ford Fiesta RRC.
Kubica, on only his second appearance in the World Rally Championship, overcome a handbrake problem early in the day and rounded off the morning loop of stages eager to go faster.
“It’s going well but I wanted more speed,” he said. “We drove most of the last test in fifth gear because we didn’t have enough power to pull sixth. But I guess that’s the same for everyone. It's going quite well for us.”
Behind Kubica, Protasov remains under pressure from Qatari driver Abdulaziz Al-Kuwari, who is just 5.9sec further back in third in another Fiesta RRC - despite contending with a broken anti-roll bar and overheating brakes.
Indonesian driver Subhan Aksa is fourth, 53.1sec back, in another Fiesta RRC. Ukrainian Oleksii Kikireshko rounds off the top five, 37.6sec further back in his Mini RRC after going off the road on SS3.
Fiesta RRC driver Lorenzo Bertelli retired from sixth place with a broken cross-member on SS5.
Kubica photo special: Head to the WRC Facebook page to a see our album of Kubica pictures from the Acropolis so far.