Heavy rain in Toronto meant that afternoon qualifying on Friday was a complete wash-out, with none of the 23 drivers able to complete a flying lap of the 11-turn, 1.755-mile temporary street course.
The rain started to fall an hour before the scheduled 2.45pm starting time for the session, and by the time practice officially started the standing water on the circuit made any flying laps a complete impossibility. With the rest of the weekend forecast to be dry there was little incentive for anyone to get any wet weather experience at the risk of damaging their cars.
Ganassi's Scott Dixon did take the opportunity to take the #9 car out on a very careful shakedown lap following the electrical problems that caused it to grind to a halt in the final moments of the earlier morning session, but other than that there were no takers and race control called an early end to proceedings.
"We had some electrical issues during today's first session, but the team worked really hard to get it fixed," Dixon explained. "It's unfortunate that we weren't able to get back on-track for a full session for the second practice, but we were able to get the car out for a quick in and out lap to make sure the issue we had in the morning was fixed. We're looking forward to making sure we're good before qualifying in tomorrow's first practice."
The afternoon practice washout meant that Juan Pablo Montoya's practice 1 time of 1:00.6343s (104.198mph) stood as the best lap of the day. He had been 0.1579s clear of his Penske team mate Simon Pagenaud, despite the Colombian getting a late start and only turning eight laps in the session.
"We went out, didn't get in many laps because we had a problem with the brakes, but the speed was there," he said. "It's encouraging, but with the rain it just makes it hard because it washes away any rubber we put down and tomorrow we have to start from zero."
CFH Racing duo Josef Newgarden and Luca Filippi were third and fourth fastest for the day ahead of KVSH Racing's Sebastien Bourdais who was able to finish just ahead of the second brace of Penske drivers with Will Power just edging Helio Castroneves out of the top six.
"I think we had a good first session. Along with Luca, the whole team rolled off the truck really well, which is important," said Newgarden. "It would've been cooler if we were 1-2, but it's just the first practice. It doesn't really mean anything. Hopefully we can roll that into tomorrow and be solid. It would be nice to get a good event for us."
"It was very good from the very beginning," concurred Filippi. "Me and Josef, we had the opportunity to push and be at the top; that was important. Also the fact that we now found a very good baseline, a very good setup for street courses. I think in Detroit we didn't show our performances, but I think we were competitive. So far a very clean weekend. We came with a good car and I knew the circuit, so here we are. I just hope we can continue on this level. I think so."
Rahal Letterman Lanigan's Graham Rahal was the only Honda runner to crack the top ten in the timesheets by the time the chequered flag had called time on proceedings.
"I don't think we got the ultimate time out of it but we were still the fastest Honda and right up there in the mix so I'm pretty pleased," Rahal noted. "I obviously wish we would have gotten the second session in but the weather didn't cooperate.
"We have seen a lot of rain this year unfortunately but the weather looks good for the next couple of days so I'm excited to get back out there," he added. "The track was rough but really similar to previous years so hopefully we can get back out there and continue to improve, have a good qualifying session and good race."
He will get his chance with a third 45-minute session planned for Saturday morning at 10.40am (3.40pm BST) before qualifying in the afternoon at 2.30pm (7.30pm BST), which will follow the usual three-round elimination format used by the series for street and road course events. The weather is expected to be overcast, but dry.
The 85-lap Honda Indy Toronto will get the green flag on Sunday afternoon at just after 3.30pm (8.30pm BST) when the forecast is for a dry and brighter day.
See full practice 1 times from the streets of Toronto.