IndyCar title contenders Will Power and Ryan Hunter-Reay believe that Friday's evening's second practice session will offer the best guide as to who will be in the strongest position going into Saturday's season finale at Fontana.
Extremely high temperatures above the 100-degree mark and changing wind conditions made for a difficult qualifying session, although the two-mile layout's grip levels change dramatically as the day goes on. Power admitted that the handling characteristics of his Penske Dallara-Chevrolet in qualifying were completely different to how they had been both during practice and in testing earlier in the week.
"It was very unpredictable," he said. "The wind changes, the whole track changes. I had totally different balance to what I had all weekend.
"I'm hoping to finish [practice] tonight thinking, 'OK, we're in good shape.' But just based on today alone, after running two days of testing, suddenly everything has changed again. It's 45 minutes [of practice]. We'll try to make the most of it."
"This track has been changing every session, every lap," he said. "The heat today... this is like Vegas heat. It's just constantly changing.
"One thing for sure, it's going to be cooler tonight. I think everybody will get the best read tonight. That's when you're going to see who is racy."