Rahal’s team won the race in 2020 with Takuma Sato, and Bobby’s son Graham Rahal showed frontrunning pace in 2021.
But three of the squad’s quartet of cars failed to make the top 30 places in Saturday’s qualifying, so Graham Rahal, Christian Lundgaard and Jack Harvey will face a last-chance qualifier session later today against Dale Coyne Racing’s rookie Sting Ray Robb.
Its fourth entry for Katherine Legge is guaranteed to start the race in 30th next Sunday.
“Naturally, I feel bad for the drivers,” Rahal Sr told NBC Peacock. “The crew has been working very hard and there’s just something we’re missing here.
“We’ve made some improvements today, and two of our cars are going to be in at the end of the day, but we’d like to get all three in.
“We need to find some more pace, Graham had too much understeer on his first run with this set-up, so that cost some speed. We’ll just keep at it.”
When asked what’s happened, Rahal replied: “That’s the $64,000 question! These cars are really no different to what they were in 2020, and we’re going as fast now as we were then. We’re just missing something a little bit.
“Graham says he’s happy with his race car from Friday, but we’ll keep picking away at it. We’ve been here before, and it’s no fun, and plenty of people have been in this situation some time.
“Roger [Penske] didn’t qualify two cars in ’95, I didn’t qualify in ’93 – it happens to everybody. I’ll be glad when the day’s over, that’s for sure.”
In the final practice session for the four last-chance cars on Sunday, Lundgaard set the fastest lap of 231.075mph ahead of Rahal, Robb and Harvey.
In the four-lap averages, on which qualifying will be decided, Lundgaard was quickest at 230.562mph, ahead of Rahal and Robb, with Harvey the slowest at 229.911mph.
“We’ve changed a lot of things, and we’re fastest of the four cars, but it’s frustrating,” said Lundgaard. “It’s not the position we want to be in, but we’ll keep digging.”