Penske recruit Josef Newgarden led the way on the first day of IndyCar's pre-season test at Phoenix.
Newgarden set a 19.351-second lap in the opening three-hour session, and finished Friday as the only driver in the 190mph bracket.
Until the final 20 minutes of the daylight session, Sebastien Bourdais led Ed Jones in a Dale Coyne Racing one-two, but a flurry of late times on new tyres dropped them down the order.
Newgarden's former boss and team-mate Ed Carpenter wound up as his closest challenger, 0.014s adrift.
"I think we had a pretty good start to today," said Newgarden.
"The car was really great off the truck, so we didn't have to do too much.
"We just got into our programme and had a pretty easy start."
The evening session offered team conditions most representative of what they will race in at Phoenix in April.
Marco Andretti led the way as Honda-powered drivers filled the top six places.
Andretti's 19.454s lap put him third in the overall order, shading Graham Rahal, while Will Power and JR Hildebrand completed the top six with times set in the afternoon.
Honda runners Takuma Sato, Scott Dixon, Bourdais, Alexander Rossi, Charlie Kimball, Tony Kanaan and Jones filled seventh through to 13th in the order.
Reigning champion Simon Pagenaud was 14th in his Chevrolet-powered Penske, with a 19.737s time from the evening session.
The test continues with two more sessions on Saturday.