Rookie Carlos Munoz shot to the top of the speed chart in Indianapolis 500 practice Thursday with a lap at 225.163 mph, the fastest through the first six days of practice.
The Andretti Autosport driver turned the fast lap in the final 10 minutes of practice.
Defending series champion Ryan Hunter-Reay was second in 225.006.
Munoz and Hunter-Reay joined teammate Marco Andretti (225.100), and Helio Castroneves (225.075) as the only drivers to top the 225 mark.
Three of the top four practice speeds have been recorded by Andretti Autosport drivers. Andretti was third-fastest Thursday at 224.882, Scott Dixon was fourth at 224.468, and Castroneves fifth at 224.457.