Pagenaud leads Saturday practice
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| Simon Pagenaud continues to be quick at Sonoma |
Team Penske's Simon Pagenaud placed the No. 1 DXC Technology Team Penske Chevrolet atop the time sheets in Saturday practice for the GoPro Grand Prix of Sonoma. The defending Verizon IndyCar Series Champion and Sonoma winner was 0.1125s ahead of Scott Dixon. Dixon, a three-time Sonoma winner, sits a mere three points behind championship leader Josef Newgarden entering tomorrow's season finale.
Will Power, Newgarden, and Helio Castroneves rounded out the top-five.
RESULTS 
| P | No | Name | FTime | Diff | Gap | FL | Laps | FSpeed | Engine | Team |
| 1 | 1 | Simon Pagenaud | 1:16.033 | –.—- | –.—- | 3 | 8 | 112.925 | Chevy | Team Penske |
| 2 | 9 | Scott Dixon | 1:16.145 | 0.1125 | 0.1125 | 3 | 9 | 112.758 | Honda | Chip Ganassi Racing Teams |
| 3 | 12 | Will Power | 1:16.161 | 0.1280 | 0.0155 | 2 | 9 | 112.735 | Chevy | Team Penske |
| 4 | 2 | Josef Newgarden | 1:16.297 | 0.2644 | 0.1364 | 3 | 10 | 112.533 | Chevy | Team Penske |
| 5 | 3 | Helio Castroneves | 1:16.478 | 0.4453 | 0.1809 | 3 | 9 | 112.267 | Chevy | Team Penske |
| 6 | 26 | Takuma Sato | 1:16.560 | 0.5268 | 0.0815 | 7 | 7 | 112.148 | Honda | Andretti Autosport |
| 7 | 15 | Graham Rahal | 1:16.637 | 0.6043 | 0.0775 | 13 | 14 | 112.034 | Honda | Rahal Letterman Lanigan Racing |
| 8 | 28 | Ryan Hunter-Reay | 1:16.647 | 0.6145 | 0.0102 | 5 | 7 | 112.019 | Honda | Andretti Autosport |
| 9 | 27 | Marco Andretti | 1:16.699 | 0.6662 | 0.0517 | 5 | 8 | 111.944 | Honda | Andretti Autosport with Yarrow |
| 10 | 10 | Tony Kanaan | 1:16.710 | 0.6766 | 0.0104 | 2 | 8 | 111.929 | Honda | Chip Ganassi Racing Teams |
| 11 | 18 | Sebastien Bourdais | 1:16.767 | 0.7346 | 0.0580 | 2 | 7 | 111.844 | Honda | Dale Coyne Racing |
| 12 | 98 | Alexander Rossi | 1:16.768 | 0.7349 | 0.0003 | 2 | 10 | 111.844 | Honda | Andretti Herta Autosport with Curb-Agajanian |
| 13 | 8 | Max Chilton | 1:17.017 | 0.9846 | 0.2497 | 13 | 13 | 111.481 | Honda | Chip Ganassi Racing Teams |
| 14 | 83 | Charlie Kimball | 1:17.127 | 1.0942 | 0.1096 | 11 | 15 | 111.323 | Honda | Chip Ganassi Racing Teams |
| 15 | 19 | Ed Jones | 1:17.148 | 1.1150 | 0.0208 | 11 | 12 | 111.293 | Honda | Dale Coyne Racing |
| 16 | 20 | Spencer Pigot | 1:17.209 | 1.1760 | 0.0610 | 3 | 13 | 111.205 | Chevy | Ed Carpenter Racing |
| 17 | 5 | James Hinchcliffe | 1:17.218 | 1.1846 | 0.0086 | 2 | 11 | 111.192 | Honda | Schmidt Peterson Motorsports |
| 18 | 7 | Jack Harvey | 1:17.265 | 1.2317 | 0.0471 | 2 | 12 | 111.125 | Honda | Schmidt Peterson Motorsports |
| 19 | 14 | Carlos Munoz | 1:17.284 | 1.2507 | 0.0190 | 13 | 16 | 111.097 | Chevy | AJ Foyt Enterprises |
| 20 | 4 | Conor Daly | 1:17.363 | 1.3304 | 0.0797 | 13 | 13 | 110.983 | Chevy | AJ Foyt Enterprises |
| 21 | 21 | JR Hildebrand | 1:17.368 | 1.3355 | 0.0051 | 16 | 20 | 110.976 | Chevy | Ed Carpenter Racing |
| 22 | 13 | Zachary Claman DeMelo | 1:17.845 | 1.8119 | 0.4764 | 10 | 16 | 110.296 | Honda | Rahal Letterman Lanigan Racing |