Lawson ended the opening hour of practice in Mexico ninth fastest with a best time just over a second off the pace laid down by George Russell.
Yuki Tsunoda is the other RB was third fastest, seven-tenths shy of the lead Mercedes.
Times alone were hardly indicative as the session was interrupted by a sizeable shunt for Alex Albon and Oliver Bearman.
The ensuring red flag and the lack of Free Practice 2 in effect (it was given over to Pirelli for tyre testing) made it difficult to establish a direct comparison between teams.
Nonetheless, feedback on the opening day was positive in Lawson’s opinion.
“It’s good. I think for the team, it’s been a very positive day,” the 22-year-old observed.
“Obviously, we’ll find out in quali, but on Friday at least the step we made last week is also transitioning into this weekend, which is nice.
“From our side, we have a little bit more to find as well.”
RB arrived at the circuit this year fresh off a points-scoring result for Lawson in the United States last weekend, where the New Zealander stormed through from 19th on the grid to ninth at the chequered flag.
That result came on a Sprint weekend, leaving just an hour of practice before competitive running commenced.
This weekend, F1 has reverted to its traditional format of three practice sessions preceding qualifying and then the race.
However, Free Practice 2 was used as a tyre test, with Pirelli giving teams specific run plans.
That meant they had mandated tyre sets and fuel loads and could not change the car’s set-up during the session, which extended from 60-minutes to 90.
“Obviously, for me, it’s probably quite valuable to be able to do that extra track time, even if it’s not on the same tyre, or most of its long-running.
“It’s just good to be in the car driving for an hour and a half.”
Lawson ended the day with 54 laps to his name around a circuit he’d never driven and is now looking to build on a positive Friday, with another points finish in Sunday’s race the ultimate goal.
“That’s definitely the target,” he said.
“We have a little bit of time to find but we have a little bit of time in the morning to [do] that.
“By quali, hopefully, we have a car that’s in a good window [and] we can hopefully fight for points.”