The three-time Supercars champion started 10th and finished eighth but wanted more than that out of his race.
At the start, McLaughlin moved up to ninth at Turn 2 and gained two more positions when Alex Palou lightly hit Marcus Armstrong's car, causing the #11 Chip Ganassi Racing car to spin and delaying the IndyCar points leader in the process.
McLaughlin moved up to sixth on Lap 12 at Devlin DeFrancesco's expense and remained in that position once the entire field made their first pit stops under green.
As eventual race winner Scott Dixon's strategy began to unfold, McLaughlin found himself down in seventh place, which became eighth after Will Power moved past his team-mate on Lap 68.
McLaughlin remained in eighth place for the rest of the race, finishing four-and-a-half seconds behind Palou and just over 22 seconds adrift of Dixon.
Gaining any positions at all was at a premium for the McLaughlin-termed Insurance Wagon, and that fact showed in McLaughlin's expression on pit road after shaking hands with his crew.
“We swung a lot of things at the car this weekend and we made it better, but this place just bamboozled me a little bit,” said McLaughlin.
“Like, just don't feel like I've got my handle on it and got to do a lot of study now just to work hard and get better here.
“Will [Power] came through and he was pretty quick. We've got to look at that.
“So yeah, it's frustrating. You come here and you're sort of just a field filler you know?
“It's unfortunate, but proud of the team, proud of the hard work, but we've just got to keep working and getting better, and especially at this place.”
IndyCar's race on the IMS road course was held on the afternoon prior to that of the NASCAR Cup Series.
That race was Shane van Gisbergen's second start in the top tier of NASCAR, ahead of an expected switch to the category in 2024, while Brodie Kostecki was on debut.
McLaughlin, who was set to listen to the race on the radio as he drove from New York with his dog, is all for van Gisbergen's career change, even if the pair aren't competing against each other again.
“Whatever [van Gisbergen] wants to do, I just think he should be in America,” remarked the second most-recent three-time Supercars champion.