Colton Herta continued his momentum from his Laguna Seca victory over to the Streets of Long Beach, going fastest in the first practice session ahead of the Acura Grand Prix of Long Beach. Championship leader Alex Palou led all of the title contenders, as he finished third.
Drivers found themselves testing the limits of the track throughout the session, but after a couple of taps with the wall, Oliver Askew brought out the first red flag of the day with 20 minutes remaining as he broke the rear tow link.
Another red flag came out just inside 10 minute remaining as Scott Dixon who went wide in turn one, locking up his left front. Dalton Kellett had a moment on the other end of the track with turn nine as a bump on the outside of the corner upset his car.
Cars got out with five minutes remaining to complete the final laps of their practice runs.
Simon Pagenaud too had an off moment in turn nine, but by the end of the session found himself as the top Team Penske car going second fastest. Palou looked comfortable finishing in third on his Long Beach debut, and Arrow McLaren SP showed pace with a car in fourth place, but it was that of Felix Rosenqvist.
Patricio O’Ward, who is competing for the championship, struggled with a sixteenth place finish and said post-session that his struggles today were reminiscent of those last weekend at Laguna Seca.
Though it was announced earlier today that Romain Grosjean will take the seat currently occupied by Ryan Hunter-Reay next season, “Captain America” let everyone know he wasn’t finished yet with a fifth place practice finish to start the weekend off right. Grosjean, still with Dale Coyne Racing with Rick Ware Racing, finished eleventh after spending time in the top five during the session.
Helio Castroneves finished the session sixth for Meyer Shank Racing, with Rookie of the Year contender Scott McLaughlin finishing seventh in his first session at the track.
James Hinchcliffe and Alexander Rossi finished eighth and ninth respectively, ensuring that all four Andretti cars were represented inside the top ten. Within the last ten minutes of the session, Andretti cars sat in the top four positions before others set their fast laps.
Josef Newgarden, the underdog title contender this year, was another victim of the bump in turn nine. About halfway through the session, the two-time series champion found himself backwards as he locked up entering the corner. After a long drift, he was able to keep it out of the barriers and carry on to finish tenth fastest in practice.
Charlie Kimball makes his return to the series this weekend with A.J. Foyt Enterprises, finishing the session twenty-fourth.
Second practice for the Acura Grand Prix of Long Beach will take place on 25 September at 1200 EST / 0900 PST / 1700 BST.
Acura Grand Prix of Long Beach Practice 1 Results
| RANK | CAR NO. | DRIVER | NAT | TEAM | BEST TIME |
| 1 | 26 | Colton Herta | USA | Andretti Autosport | 01:09.268 sec. |
| 2 | 22 | Simon Pagenaud | FRA | Team Penske | 01:09.433 sec. |
| 3 | 10 | Alex Palou | ESP | Chip Ganassi Racing | 01:09.455 sec. |
| 4 | 7 | Felix Rosenqvist | SWE | Arrow McLaren SP | 01:09.487 sec. |
| 5 | 28 | Ryan Hunter-Reay | USA | Andretti Autosport | 01:09.515 sec. |
| 6 | 06 | Helio Castroneves | BRA | Meyer Shank Racing | 01:09.570 sec. |
| 7 | 3 | Scott McLaughlin (R) | NZL | Team Penske | 01:09.621 sec. |
| 8 | 29 | James Hinchcliffe | CAN | Andretti Steinbrenner Autosport | 01:09.627 sec. |
| 9 | 27 | Alexander Rossi | USA | Andretti Autosport | 01:09.794 sec. |
| 10 | 2 | Josef Newgarden | USA | Team Penske | 01:09.855 sec. |
| 11 | 51 | Romain Grosjean (R) | FRA | Dale Coyne Racing w/ Rick Ware Racing | 01:09.880 sec. |
| 12 | 12 | Will Power | AUS | Team Penske | 01:09.991 sec. |
| 13 | 9 | Scott Dixon | NZL | Chip Ganassi Racing | 01:10.053 sec. |
| 14 | 18 | Ed Jones | UAE | Dale Coyne Racing w/ Vasser-Sullivan | 01:10.114 sec. |
| 15 | 60 | Jack Harvey | GBR | Meyer Shank Racing | 01:10.175 sec. |
| 16 | 5 | Pato O’Ward | MEX | Arrow McLaren SP | 01:10.245 sec. |
| 17 | 8 | Marcus Ericsson | SWE | Chip Ganassi Racing | 01:10.315 sec. |
| 18 | 14 | Sebastien Bourdais | FRA | A.J. Foyt Enterprises | 01:10.378 sec. |
| 19 | 15 | Graham Rahal | USA | Rahal Letterman Lanigan Racing | 01:10.511 sec. |
| 20 | 21 | Rinus VeeKay | NED | Ed Carpenter Racing | 01:10.737 sec. |
| 21 | 30 | Takuma Sato | JPN | Rahal Letterman Lanigan Racing | 01:10.767 sec. |
| 22 | 59 | Max Chilton | GBR | Carlin | 01:10.784 sec. |
| 23 | 20 | Conor Daly | USA | Ed Carpenter Racing | 01:10.903 sec. |
| 24 | 11 | Charlie Kimball | USA | A.J. Foyt Enterprises | 01:11.061 sec. |
| 25 | 77 | Callum Ilott (R) | GBR | Juncos Hollinger Racing | 01:11.118 sec. |
| 26 | 45 | Oliver Askew | USA | Rahal Letterman Lanigan Racing | 01:11.225 sec. |
| 27 | 48 | Jimmie Johnson (R) | USA | Chip Ganassi Racing | 01:11.437 sec. |
| 28 | 4 | Dalton Kellett | CAN | A.J. Foyt Enterprises | 01:11.796 sec. |