Mercedes focused its afternoon attentions on performance runs, with Mazepin reporting no issues for driver and auto through the session - despite having his running late in the morning session cut short by a spin at Turn 11 that brought out the red flags.
"Importantly it was a successful day on track too, we gathered most of the data we set out to collect", he added. "Everyone in the team is working so hard and you can feel that when you sit in this vehicle".
Before Albon's late lap it looked like Ferrari were once again going to be second fastest, and also with a less familiar name as Antonio Fuoco posted a 1m17.284s. Fuoco - previously a member of the Ferrari Driver Academy - set his best time on the C4 tyres and led three cars covered by a little over 0.1s as he ended up third. Pirelli worked through prototype constructions and compounds aimed at protecting the tyres from overheating while running behind another auto - a common complaint from drivers in recent years.
Jack Aitken was among four F2 drivers taking part in Wednesday's test and was behind the wheel of the Renault.
McLaren split running between two of its simulator drivers, with Oliver Turvey managing 52 laps before the lunch break. That followed a delay caused by Dan Ticktum in the Red Bull, who stopped on the exit of Turn 10 and was limited to 79 laps across the day.
"Driving the McLaren Formula One vehicle was an incredible opportunity for me today", Sette Camara said. "I think it's going to be very close all year, which is fantastic for us because they're pushing both sides of the garage along, making the vehicle faster and the team operate at a higher level".
Leclerc was conducting a Pirelli test on Wednesday, while Ferrari will hope to have found solutions to their F1 2019 problems with chief rivals Mercedes winners of all five races so far this season.
The F1 paddock will reconvene in Monte Carlo in a week's time to kick off the Monaco Grand Prix weekend.