IndyCar spring training test: Colton Herta stays on top at Austin

Herta's 1m46.6258s lap of the United States Grand Prix Formula 1 venue - which hosts IndyCar for the first time this season - was 1.4 seconds quicker than his nearest opposition when he set it with an hour and seven minutes of the three-hour afternoon session to run.

Penske's Will Power whittled that deficit down to 0.48 seconds three laps from the end, but then spun coming into the final turn.

"I'm super happy with how the day went," said Herta, the 2018 Indy Lights runner-up and now sole driver for the Andretti-affiliated HSR team after Patricio O'Ward's last-minute departure.

"We did some great things to the car and I'm very happy with how the boys got everything together in time for this test.

"Everyone did a fantastic job and there were no issues with the car; it was perfect. We kept chipping away and kept finding time.

"By the end of the day, we were quickest by quite a margin. I can't wait for tomorrow now."

Power's part-time team-mate Helio Castroneves was allowed to halt his full-fuel load runs in the additional fourth Penske Dallara-Chevrolet to jump up to third place, albeit a second off the ultimate lap from Herta.

Rookie Felix Rosenqvist outpaced Chip Ganassi Racing Dallara-Honda team-mate Scott Dixon by 0.0023s to grab fourth spot, while Simon Pagenaud made it three Penske drivers in the top six just behind them.

Alexander Rossi was fastest of the Andretti Autosport drivers in seventh place, a couple of tenths faster than Graham Rahal - who showed major improvement from Rahal Letterman Lanigan Racing's form at the Laguna Seca test last Friday.

Dale Coyne Racing's Santino Ferrucci slotted into ninth ahead of Ed Carpenter Racing driver Spencer Pigot who, along with Rosenqvist, turned the most laps of the session with 38.

Marcus Ericsson and James Hinchcliffe were 11th and 12th for Schmidt Peterson Motorsports, followed by Josef Newgarden in the final Penske entry.

Ryan Hunter-Reay, whose car had to be towed into the pits early in the three-hour session, ended up 15th between his Andretti Autosport team-mates Zach Veach and Marco Andretti.

Carlin's two cars were 18th and 21st with RC Enerson and Max Chilton, with ECR's Ed Jones pipping his 2017 Dale Coyne Racing team-mate Sebastien Bourdais to 19th.

Kyle Kaiser's Juncos Racing entry was 24th, 3.25s off Herta's pace after missing the morning session due to clutch problems.

Tony Kanaan's AJ Foyt Racing Dallara-Chevrolet broke its gearbox, so he only completed six laps and brought up the rear of the 25-car field.

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