Patrick heads Motegi practice

Patrick lapped the 1.5-mile oval in 26.9585 seconds - 202.979 mph - in the No. 7 Andretti Green Racing Honda/Dallara. Super Aguri Panther Racing's Kosuke Matsuura, the only Japanese driver in the IndyCar Series, was second-fastest with a lap of 202.472 mph.

Patrick said the quick start bodes well for her chances to post her first IndyCar Series victory.

"It follows along with a saying that my dad has, 'However you unload is how you run.' We unloaded with a good car, and it's been a fairly straightforward day," Patrick said.

"The team gave me a good car to start with, and we made small changes during the morning session. In the afternoon practice, we didn't change anything."

Matsuura said his ability to run well alone gives him confidence for running in traffic during the race.

"I could run pretty well alone, so I want to run in traffic during the practice session tomorrow," he said.

"The team has been working so hard on my car to win the race in my home country, so I am looking forward to the qualifying tomorrow and hopefully get a good starting position."

Defending race winner Helio Castroneves (202.295 mph), Tony Kanaan (201.972 mph) and two-time Motegi winner Dan Wheldon (201.444) rounded out the top five as teams battled cool and windy conditions throughout both practice sessions.

Vitor Meira crashed in the opening minutes of the first practice session but was not injured.

Teams will continue practice Friday morning before qualifying Friday afternoon.