Indianapolis 500 polesitter Andretti holds top spot in Sunday practice

Soon after Andretti's narrow victory over Dixon in qualifying, IndyCar ran a two-hour and 30 minute session in which the turbos were wound down to the permitted race-day boost of 1.3-bar and with race-day downforce levels.

While six drivers turned 100 laps or more, Andretti turned just 27 - and yet the 21st of these was the fastest of the session, a 224.122mph effort which just shaded the best effort of Team Penske-Chevrolet's three-time Indy 500 winner, Helio Castroneves.

The Brazilian was one of four Chevrolet cars in the Top 10, which seemed stronger relative to their Honda-powered rivals with the boost dialled back and in traffic, compared to qualifying trim.

Chip Ganassi Racing's Scott Dixon, who placed unintentionally stole the show with a 218mph spin coming off Turn 4 after hitting a bump.

Dixon clipped the outside wall with his rear wing, spinning across to hit the pitwall.

Less than hour later, the #9 Chip Ganassi Racing crew had his car repaired and ready to return to action - and the 2008 Indy 500 winner briefly launched to the top of the timesheets with the first lap into the 223mph bracket.

Ryan Hunter-Reay of Andretti Autosport was fourth quickest ahead of Dale Coyne Racing with Vasser-Sullivan's Santino Ferrucci, who won the 2019 Indy 500 Rookie of the Year award.

Conor Daly, as he had on Wednesday and Thursday, looked very strong in traffic for the Chevrolet-powered Ed Carpenter Racing outfit, as did his team owner Ed Carpenter who has suffered some uncharacteristic struggles with his car's handling this past week.

Rookie Alex Palou made it two Coyne cars in the Top 10, but the third one - co-entered by Rick Ware Racing/Byrd/Belardi - was not in action, as its driver James Davison was competing in the NASCAR race at Daytona.

Both Fernando Alonso and one of his Arrow McLaren SP-Chevrolet teammates Pato O'Ward turned 115 laps - more than anyone else - and both looked comfortable in traffic and able to pass.

Alonso, however, did have a half-spin-and-stall exiting his pit box during the session.

Indianapolis 500 Sunday practice results