Despite having appeared pessimistic about his chances of landing a seat for the 'greatest spectacle in racing', John Andretti will attempt to qualify for his ninth Indianapolis 500 having replaced Jay Howard in the #24 Roth Racing car for Pole Day.

The NASCAR regular, who started 24th and finished 30th in last year's race with Panther Racing, has been installed in the #24 in the hope that his experience can bring the small two-car operation up to speed after rain depleted the week's practice opportunities for Howard and owner-driver Marty Roth.

"As a result of the days lost due to weather, and losing our chief engineer days before the start of this month, we found ourselves behind the eight-ball," team president Margaret Roth said. "John brings with him a wealth of experience, which can help us build two competitive cars for the 500. Jay will be back at Milwaukee. He has our full support. He's a great driver."

Howard joined Roth Racing after sitting out most of 2007, despite being the reigning Indy Pro Series champion. His four races so far this season have yielded finishes of 22nd, 14th, 13th and 13th , but he admitted to struggling to pin down the #24 after missing two days of practice this week.

"We were sort of counting on the hours this afternoon," he said as more rain interrupted Fast Friday, "I think that's important for us, but I think we'll be fine. It's always a little bit harder when you come out on a new run and there's cars circulating. It does make it difficult to get in a groove without trying to screw anyone else up. Several times I went down to the apron, just to try to stay out of people's way. There's other drivers out there not doing the same for me, which isn't very nice. That kind of makes it difficult trying to get up to speed, get the tyres up to temperature and all that. To be honest, I don't know. I doubt we're going to run any qualifying attempts."

Andretti, cousin of Andretti Green Racing co-owner Michael Andretti, has a best finish of fifth at Indianapolis, from 1991, but has not turned a lap so far this May.

"I want to feel it out a little bit, and see what we can do," he said as he prepared to join Pole Day practice.