Championship leader Max Verstappen only managed to set the fifth fastest time, as the Dutchman seeks his first race win since the Spanish GP seven races ago.
His team-mate Sergio Perez, who has struggled to perform consistently this season, seemed to re-discover pace during the initial practice sessions in Baku.
Initially, Perez and Carlos Sainz found themselves under FIA investigation following FP2 on Friday, with the Ferrari star summoned for impeding the Red Bull into Turn 13.
The incident was investigated due to Perez moving to the ‘right at a high-speed section of the track which could have been potentially dangerous’ to avoid Sainz.
Sainz moved to get out of the Red Bull's path, avoiding a collision. The Spaniard didn't come out of the incident entirely unscathed however and received a warning from the sport's governing body.
However, the pair have once again come under scrutiny from the FIA, with Perez summoned by the stewards following FP3 for this time impeding Sainz.
The Ferrari was on a fast lap when he was confronted by the Mexican driving slowly into Turn 15, with Sainz forced to cut the corner to avoid a collision.
Speaking to Sky Sports after the session, Red Bull team principal Christian Horner discussed the incident and his opinion on what the verdict should be.
“I think we didn’t give perhaps Checo the information early enough about Carlos,” Horner said.
“It wasn’t quite as bad as yesterday’s but it was almost an action replay of yesterday so I would expect a similar reverse outcome.”