Dixon lapped the 14-turn, 2.439-mile IMS road course in 1m10.9851s in the 30-minute session, which acts as the warm-up for tomorrow’s race.
The session took on more importance after a remarkable qualifying session beforehand, in which title contenders Alex Palou (Ganassi) and Josef Newgarden (Penske) could only manage eighth and 19th on the grid respectively.
Firestone has brought a harder compound this weekend than it did for May’s event here, which caused chaos for some – most notably Team Penske, with Scott McLaughlin the best of its runners in 11th (although he’ll start 10th), with Will Power in 16th.
“Basically the red tyre [alternate] is a primary from another circuit,” explained Dixon.
Newgarden’s day turned even more sour when he was given a 10-minute penalty in this session for missing the driver weigh-in. He responded by going fastest with 1m11.7878s after 10 of his 20 minutes available.
Former race winner here Rinus VeeKay beat that with 1m11.4844s for Ed Carpenter Racing, before Callum Ilott set 1m11.4315s and then Palou grabbed P1 with 1m11.1365s.
Dixon – who will start 15th after also struggling in qualifying – went to the top of the timesheet with four minutes to go with 1m10.9851s, ending the session fastest ahead of Palou, Penske’s Scott McLaughlin, Illot, Kyle Kirkwood (who’ll start 13th for Andretti Autosport), VeeKay, Colton Herta (starting 11th for Andretti) and Marcus Ericsson (Ganassi – who suffered more clutch issues in this session).
Pole-winner Graham Rahal was only 17th in this session.
Tomorrow’s race starts at 2:00pm ET.