Ryan Hunter-Reay

SONOMA, Calif. – Andretti Autosport enjoyed its best Friday of the season after all four drivers showed strong pace during dual Verizon IndyCar Series practice sessions for the GoPro Grand Prix of Sonoma.

Marco Andretti kicked it off with a stout lap during first practice, coming within 0.131 of a second of pacesetter Helio Castroneves and showcasing the speed he’s yearned for all season. Andretti wound up the day 11th on the combined speed chart with a best lap of 1 minute, 17.3286 seconds (111.033 mph) in the second practice. The 29-year-old driver of the No. 27 Snapple Honda came away satisfied, but admitted that the weekend is best served as an experiment as his team looks toward next year.

“Pretty good, definitely happy with our pace here as a team,” said Andretti, the 2006 winner at Sonoma Raceway when he was a series rookie. “We know what we’ve done all season’s not right, so we’re almost using this weekend as a test session. I think if we hit on something, I’ll be really optimistic for next season.”

Winning or stepping onto the podium this weekend could go a long way to help Andretti, mired at 17th place in the point standings, try and build momentum leading into 2017.

Alexander Rossi ended the opening session 11th fastest, but by the end of the day jumped to fifth (1:17.0817, 111.388 mph) behind teammate Ryan Hunter-Reay, driver of the No. 28 DHL Honda. The second-place finisher in the last two Sonoma races, Hunter-Reay had the best day statistically among the team, placing in the top five in both sessions (best lap of 1:17.0569, 111.424 mph).

Rossi, the 24-year-old native Californian from nearby Nevada City, didn’t have any real answers as to why the Andretti foursome had the quick pace at the 2.385-mile, 12-turn permanent road course, adding that they were simply fast at last week’s Sonoma test as well.

“We learned that we were quick (at the test),” said Rossi, driver of the No. 98 Castrol Edge/Curb Honda for Andretti Herta Autosport with Curb-Agajanian.

“I'd love to tell you that we found the solutions to our problems. I think we've made small steps forward, but not as big as it appears at the moment. I think this track is just suited to us. I think Ryan's results the past two years here kind of proved that.”

Only the Indianapolis 500 presented by PennGrade Motor Oil awards double points besides the season-finale GoPro Grand Prix of Sonoma. Having already claimed the former, Rossi believes the Andretti squad will need to find even more speed if the team has any hopes of winning again Sunday.

“Being quicker than we are (is what it is going to take to win),” Rossi said. “I mean, almost a half-second gap (to Castroneves, fastest of the day at 1:16.6678) is too much. I think we have a good package. As you said, it's the best Friday as a group we've had all year.

“If we can continue that progression, continue with the pace that we've kind of shown a little bit today, then hopefully it can be a positive thing come Sunday.”

The reigning Indy 500 champion currently sits 11th in the standings, 33 points behind top Honda driver Graham Rahal. A solid finish would not only lock up Sunoco Rookie of the Year honors for Rossi, but a chance break into the top 10 in the championship and become the manufacturer’s kingpin.

Carlos Munoz, driver of the No. 26 hhgregg Honda, enjoyed a solid day after quietly working his way up to seventh by the end of the afternoon (1:17.1905, 111.231 mph). The 24-year-old Colombian and two-time Indy 500 runner-up will aim to change his poor fortunes at the track north of San Francisco.

“Everyone seemed to improve a little bit, but that happens,” Munoz said. “I think we need to be a little bit more competitive to fight for the (Firestone) Fast Six (in qualifying), but we’ll see what happens.”

A third Sonoma practice starts at 2 p.m. ET Saturday (streamed live on RaceControl.IndyCar.com, delayed NBCSN broadcast at 5 p.m.). NBCSN and the Advance Auto Parts INDYCAR Radio Network carry live coverage of GoPro Grand Prix of Sonoma qualifying (6 p.m. ET Saturday) and the 85-lap race (6:30 p.m. ET Sunday).