Herta leads opening Portland practice
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| Colton Herta |
With a lap speed of 123.115, Colton Herta led a Honda 1-2-3 sweep in opening practice for the
Grand Prix of Portland. Alexander Rossi was second, twelve-hundredths adrift of Herta with Scott Dixon third.
Series championship leader Josef Newgarden was the top Chevy in fourth, while Marco Andretti rounded out the top-five.
RESULTS
| P | No | Name | FTime | Diff | Gap | Laps | FSpeed | Engine | Points | Team |
| 1 | 88 | Colton Herta | 57.429 | –.—- | –.—- | 18 | 123.115 | Honda | 282 | Harding Steinbrenner Racing |
| 2 | 27 | Alexander Rossi | 57.554 | 0.1245 | 0.1245 | 14 | 122.849 | Honda | 517 | Andretti Autosport |
| 3 | 9 | Scott Dixon | 57.792 | 0.3629 | 0.2384 | 18 | 122.342 | Honda | 493 | Chip Ganassi Racing Teams |
| 4 | 2 | Josef Newgarden | 57.850 | 0.4211 | 0.0582 | 16 | 122.219 | Chevy | 563 | Team Penske |
| 5 | 98 | Marco Andretti | 57.901 | 0.4713 | 0.0502 | 16 | 122.113 | Honda | 254 | Andretti Herta with Marco & Curb-Agajanian |
| 6 | 5 | James Hinchcliffe | 57.948 | 0.5186 | 0.0473 | 17 | 122.013 | Honda | 316 | Arrow Schmidt Peterson Motorsports |
| 7 | 26 | Zach Veach | 57.962 | 0.5326 | 0.0140 | 18 | 121.984 | Honda | 239 | Andretti Autosport |
| 8 | 10 | Felix Rosenqvist | 58.026 | 0.5969 | 0.0643 | 26 | 121.848 | Honda | 324 | Chip Ganassi Racing Teams |
| 9 | 28 | Ryan Hunter-Reay | 58.162 | 0.7325 | 0.1356 | 17 | 121.564 | Honda | 368 | Andretti Autosport |
| 10 | 30 | Takuma Sato | 58.191 | 0.7613 | 0.0288 | 19 | 121.504 | Honda | 382 | Rahal Letterman Lanigan Racing |
| 11 | 12 | Will Power | 58.234 | 0.8050 | 0.0437 | 20 | 121.413 | Chevy | 416 | Team Penske |
| 12 | 22 | Simon Pagenaud | 58.329 | 0.9001 | 0.0951 | 18 | 121.215 | Chevy | 525 | Team Penske |
| 13 | 4 | Matheus Leist | 58.338 | 0.9088 | 0.0087 | 23 | 121.197 | Chevy | 211 | AJ Foyt Enterprises |
| 14 | 59 | Max Chilton | 58.344 | 0.9143 | 0.0055 | 17 | 121.186 | Chevy | 131 | Carlin |
| 15 | 18 | Sebastien Bourdais | 58.426 | 0.9963 | 0.0820 | 17 | 121.015 | Honda | 312 | Dale Coyne Racing with Vasser-Sullivan |
| 16 | 15 | Graham Rahal | 58.462 | 1.0323 | 0.0360 | 18 | 120.941 | Honda | 346 | Rahal Letterman Lanigan Racing |
| 17 | 60 | Jack Harvey | 58.492 | 1.0629 | 0.0306 | 19 | 120.878 | Honda | 153 | Meyer Shank Racing with Arrow SPM |
| 18 | 20 | Ed Jones | 58.501 | 1.0712 | 0.0083 | 9 | 120.861 | Chevy | 187 | Ed Carpenter Racing |
| 19 | 19 | Santino Ferrucci | 58.623 | 1.1939 | 0.1227 | 18 | 120.608 | Honda | 326 | Dale Coyne Racing |
| 20 | 14 | Tony Kanaan | 58.659 | 1.2299 | 0.0360 | 13 | 120.534 | Chevy | 258 | AJ Foyt Enterprises |
| 21 | 21 | Spencer Pigot | 58.838 | 1.4087 | 0.1788 | 15 | 120.167 | Chevy | 287 | Ed Carpenter Racing |
| 22 | 23 | Charlie Kimball | 58.989 | 1.5602 | 0.1515 | 21 | 119.859 | Chevy | 67 | Carlin |
| 23 | 7 | Conor Daly | 59.183 | 1.7535 | 0.1933 | 21 | 119.467 | Honda | 124 | Arrow Schmidt Peterson Motorsports |