Sato, who started 90 Formula 1 grands prix from 2002-2008 for Jordan, BAR/Honda and Super Aguri, is one of Alonso’s five Andretti Autosport teammates this month, and says the Spaniard has got up to speed rapidly.

“It’s very impressive,” Sato told motorsport.com. “It’s kind of what we expected, to be honest. Fernando is one of the best drivers in the world, and having had this much oval practice time and all the support from the team and friends and teammates, we expected him to be up to speed very quickly.”

Sato, who has been an IndyCar driver since 2010, believes Alonso has mastered giving technical feedback on ovals during this week of practice at Indianapolis. This experience included Alonso’s first chance today to try the car in qualifying trim – low drag aero, and with 1.4-bar turbo boost. He ended the day fourth fastest.

“Today is something new for him again, full boost,” said Sato. “He did drive extremely well and, actually, the feedback is proper feedback, so we talk the same language every single day after the debrief.

“He is learning, but he can feel it [the car] in the same ways. His engineer, Eric [Bretzman], has tons of experience in a big team. So we’re pretty happy. It’s nice to work with him in the same team. It’s extra attention for us and that’s always good for Michael [Andretti, team owner], so we’re very happy.”

Sato was third fastest overall on Fast Friday with a best lap of 231.969mph, one place behind teammate Ryan Hunter-Reay, and was also happy with his no-tow speed of 230.708mph.

“It was quite a good day, very productive,” said Sato. “Oval speed is sometimes a little bit artificial because some people get a tow but it was obviously good to see we were all up there, especially on the no-tow lap, which is true speed.

“I’m eighth fastest on no-tow lap, I’ll take it. Where we are in terms of the car setup, I’m feeling better and enjoying working well together with Andretti Autosport.”