Andretti leads first Indianapolis 500 practice day, Alonso 19th

Andretti posted a 226.338mph average speed on the 31st of his 47 laps, to grab top spot by over 1mph, ahead of fellow Honda runner Scott Dixon, who also set the fastest speed without the aid of a tow from another car.

Top Chevrolet speed went to Ed Carpenter, who earned third place with a 224.969mph, ahead of a trio of Hondas - Sebastien Bourdais, Ryan Hunter-Reay and Graham Rahal.

However, Rahal suffered the major problem in the second half of the session, as his engine appeared to let go with 45mins left on the clock.

Two-time Formula 1 world champion Alonso was 19th overall with a best overall lap of 223.025mph, on the 15th of his 20 laps.

He was a notable absentee when the four full-time Andretti Autosport cars were lapping in the final hour, practicing drafting and setting their fastest speeds.

This was due to rear suspension issues on his McLaren Honda Andretti entry.

Alonso's fastest speed without the aid of a draft was a 219.265mph.

All entries except Buddy Lazier ran on Monday, although Alonso's fellow Andretti newcomer Jack Harvey was absent for the final two hours after a crash caused by a failure in his car's steering.

Michael Shank, whose team is running Harvey's #50 entry for Michael Andretti, said: "We're not totally certain [what happened], but we're going to find out and I hope to know in a couple of hours.

"Not the day we wanted to start with today, a couple of issues right away.

"The car has actually got some speed in it which is good, and the balance is pretty good.

"Andretti Autosport has a really good technical package around this place, so we're going to fully investigate, we'll work all night if we have to, and get back out there."

Gabby Chaves was slowest, having completed only six laps in the Harding Dallara-Chevrolet.

MONDAY PRACTICE TIMES: