The Thai-bred qualified ninth fastest at Spa, progressing into the top 10 shootouts, finishing sixth in Q1 and 10th in Q2.
But due to grid penalties for qualifying pacesetter Max Verstappen, his Ferrari rival Charles Leclerc and Alpine driver Esteban Ocon, Alban will line up sixth.
The 2020 Grand Prix of Austria, Tuscany, Turkey and Bahrain marks the first Saturday return of the former Red Bull driver’s career with Williams and Toro Rosso.
According to Williams head of performance Dave Robson, the turnaround in pace was the result of an “inexpensive” circuit-specific upgrade to the FW44 that maintained the car’s performance.
The weather conditions also played a part as the car was wind sensitive and this ended Hungarian qualifying for both Alban and teammate Nicolas Latifi by the final turn.
Robson said: “We went for a relatively cheap upgrade where we cut the rear end off the rear wing, but it worked really well.
“[It has] Maintained very good performance for that traction level.
“The other thing here is that the amount of air is low, so the car performs well and smoothly, which helps.
“When we reduce the amount of downforce, it’s useful that you still have that stability.
“Drivers generally know what they’re going to get at each corner. So, effective performance is good.”
Alban’s Q2 and Q3 laps were marred by mistakes, and his best lap time was good enough for seventh.
But this somewhat ragged approach was “nothing to lose”, knowing he would start no lower than ninth because of the penalty.
Likewise, Alphonse Q3 was sent without a drag as Williams confidently followed track evolution and wanted to ensure there was clear air to manage tire temperatures.
Running with a brand new power unit, Alban reckons the spa helped ‘hide’ the car’s flaws better than most.
He said: We know the weakness of our car. This route covers them a bit more than other circuits. So [Zandvoort, next race] Not as smiley as this week.
“We know our car likes low downforce, and when the track conditions are in a place that suits us, we can extract a good lap time from the car.”
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