Herta lapped the 2.21-mile course at 105.797mph, a lap time of 1min15.2sec, to go 0.3sec clear of teammate Jamin.

He commented afterward: ““It’s the best way to finish, especially with St. Pete right around the corner. It’s important that we’re on top here.

“We came and we bossed it, really – the whole team has been super quick. Nico has been right there with me, one-two both days. And we were the quickest no-tow time on the oval last Monday.

“But today was even more important because this was on the road course, and with St. Pete next week, we set ourselves up well.”

Jamin in turn was mere hundredths ahead of series sophomores Kyle Kaiser (Juncos Racing), Santiago Urrutia (Belardi Auto Racing) and Juan Piedrahita (Team Pelfrey).

Said Jamin: “Everything is coming together very well. We ran into two small issues today but overall we learned a lot and we’re P2 in the final test, so that is a very strong start to the season.

“My teammate is in front of me so that shows the cars are working very well and now we need to keep working hard and come on even stronger at St. Pete. I feel very comfortable with the car, my engineer and the team, so the transition from Pro Mazda is done. Now it’s time to win races!”

Patricio O’Ward, who was confirmed in the Team Pelfrey seat at least for St. Petersburg’s season-opening event, was just 0.14sec slower than the other Pelfrey entry of Juan Piedrahita. His time also put him a fraction ahead of his Pro Mazda teammate Aaron Telitz, who was confirmed at Belardi earlier this week.

Carlin’s star by some considerable margin was series newcomer Matheus Leist.

1. Colton Herta Andretti Steinbrenner Racing 1min15.2009sec

2. Nico Jamin Andretti Autosport 1:15.5004

3. Kyle Kaiser Juncos Racing 1:15.5090

4. Santiago Urrutia Belardi Auto Racing 1:15.5166

5. Juan Piedrahita Team Pelfrey 1:15.5437

6. Matheus Leist Carlin Racing 1:15.6552

7. Pato O’Ward Team Pelfrey 1:15.6894

8. Aaron Telitz Belardi Auto Racing 1:15.7195

9. Shelby Blackstock Belardi Auto Racing 1:15.7360

10. Nicolas Dapero Juncos Racing 1:15.7387

11. Dalton Kellett Andretti Autosport 1:15.9029

12. Neil Alberico Carlin Racing 1:15.9078

13. Zachary C. De Melo Carlin Racing 1:15.9987

14. Ryan Norman Andretti Autosport 1:16.2159

15. Garth Rickards Carlin Racing 1:16.5989