Seven drivers ran the P Zero Yellow medium tyres in Q2, but the Mercedes drivers were the only ones to set their fastest times on this compound - meaning they will start on it tomorrow - with Valtteri Bottas on pole and his team mate George Russell second.
Both AlphaTauri cars ran the medium tyres at the start of the final Q3 session, preserving a new set of softs for the final decisive run.
This was the shortest timed pole lap in Formula 1 since Ferrari driver Niki Lauda took pole for the 1974 French Grand Prix at Dijon. The short lap meant that finding a clear lap in the traffic was essential in qualifying, and this will be an issue in the race tomorrow as well.
Track temperatures for qualifying were similar to how they had been in FP3 (where Red Bull's Max Verstappen went fastest) at 26 degrees centigrade.
A two-stop strategy seems set to be the fastest approach to the 87-lap Sakhir Grand Prix, which is the highest lap count of the year. While the demands on tyres are a bit less than they were at the Bahrain Grand Prix, wear and degradation is still relatively high on the abrasive surface.
The fastest two-stopper should be two stints on the P Zero Yellow medium tyre of 26 laps each, plus one 35-lap stint on the P Zero White hard tyre (which could be the middle stint).
Alternatively, another good two-stopper would be one 21-lap stint on the P Zero Red soft plus two stints on the hard tyre of 33 laps each. Very close to that is a strategy with 25 laps on the medium and two stints of 31 laps each on the hard.
What's slower is using all three tyres: 23 laps on the soft, 27 laps on the medium, and 37 laps on the hard.
All of the above stints can be run in any order, and with the two frontrunners starting on the medium tyre, they have plenty of options - depending on the actual degradation rates that they encounter during the race, with track temperatures capable of falling over the course of the night race.
Mario Isola: "It was a very open qualifying session because of the very short lap, which meant that traffic was an issue and any mistakes were magnified, with the cars being so close together. Finding a gap was crucial, and all three sessions were extremely closely-fought, which should make for an exciting race tomorrow. The two Mercedes in first and second will be the only ones in the top 10 starting on the Yellow medium tyre, so it will be fascinating to see if they can turn that into an advantage for the Sakhir Grand Prix; especially at the start, with so many cars on the faster soft tyre immediately around them. All three compounds performed well, with a two-stopper set to be the quickest choice for tomorrow."
Check out our Saturday gallery from Bahrain, here.