NASCAR Cup Series star Brad Keselowski has revealed that he was once very very interested in racing in IndyCar, but those days have now passed.

The topic came to light during last weekend's event at Phoenix Raceway, where NASCAR and IndyCar shared the same venue for the weekend, merging their two racing fanbases in Arizona.

Several NASCAR stars made interesting comments regarding IndyCar throughout the weekend. Ryan Blaney wants to see more NASCAR and IndyCar double-headers, William Byron has no interest in trying IndyCar just yet, and now Brad Keselowski has offered his verdict on racing in the open-wheel series.

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Brad Keselowski on IndyCar switch

“I tested an IndyCar at Road America about 10 years ago and I loved it," Keselowski told the media at Phoenix. "I had a lot of fun.

"What’s really, really difficult is that all of my time in Cup I’ve never been with a manufacturer in the Cup Series that competes in the IndyCar Series and to go back and forth between the two is considerable pain for the OEMs that is tough to justify.

"I think that window for me has probably come and gone. There was a time where I was very, very interested, but life takes us in other places and I’m not complaining.”

Indy 500 and Coca-Cola 600 double

Over the years, we have seen some NASCAR drivers attempt the 'double', which is where they race in IndyCar at the Indy 500 and then head to Charlotte to race in the Coca-Cola 600 on the very same day.

For the last two years, we saw Kyle Larson attempt the stunning feat, but both efforts came up short due to a combination of weather and wrecks.

This year, there are currently no NASCAR drivers who have confirmed they are attempting the 'double'.

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