There was plenty of work to complete in the solitary hour of practice, with both drivers running the C1 Hard and the C3 Medium compound in FP1.
George finished that session P7, but fastest of the Medium shod runners, with Kimi, on his first visit to the Circuit of the Americas, P18.
Both drivers progressed through SQ1 needing only one lap but SQ2 proved more challenging.
Kimi improved on his second and final effort but fell an agonising 0.006s shy of progressing and ended P11.
George, using the mandatory Soft compound in SQ3, went early in the final eight-minute segment but could only manage P5.