Max Verstappen secured pole position for Sunday's Azerbaijan Grand Prix after a chaotic qualifying session that saw championship leader Oscar Piastri crash out and Carlos Sainz deliver Williams its best qualifying result in years with second place.

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Q2 didn't even last five minutes before another stoppage emerged, with Ollie Bearman just tapping the wall at Turn 2. The fourth red flag of the day waved, stopping the clock with just over 11 minutes to go in the session, and that marked both Haas drivers being knocked out of qualifying, after Esteban Ocon failed to advance out of Q1. Bearman had been showing promise in FP2 and FP3, his pace landing him in the top 10, and he was P15 in Q1.

At that time, Verstappen had set the fastest lap of the session when qualifying came to yet another halt. But it didn't take long for the McLarens to get into the mix, as well as the Mercedes duo. In the end, Verstappen had the fastest time with a 0.141-second gap over Norris, who was second fastest. And Piastri was right behind his teammate. But the biggest surprise was Lewis Hamilton being knocked out, finishing P12. It's his fifth time failing to reach Q3 this season.

Intrigue surrounded Ferrari coming into Saturday's sessions. Leclerc has secured four pole positions at this track, and Hamilton and Leclerc led FP2's timesheets. Hamilton reminded everyone on Friday that it was just practice during his post-session interview, but a change with his brakes helped him improve from FP1 to FP2.

"Every track I'm going to is the first time driving the Ferrari at that circuit, so acclimatizing to that is not easy," he said Friday. "Then we made some changes going into FP2, and the brakes finally were working perfectly. I was really able to make a quick big advantage in terms of gaining on the brakes.

"(I'm) really happy to see the progress. It just goes to show the direction we've been going as a team, really grateful for everyone's patience and everyone pushing so hard, because we're really starting to see the progress come through."

But Ferrari seemed vulnerable in Q2. Leclerc made a few mistakes before he nailed a provisional fourth-fastest lap with 90 seconds or so remaining in the session. It ended up being sixth fastest, and it's a surprise, given he brushed the barriers. Hamilton, though, was knocked out -- a deflating moment after this weekend felt like it held promise for the seven-time world champion.

It wasn't that Hamilton put together a messy lap but rather the knockout boiled down to tire choices. The seven-time world champion felt they had solid pace, telling Sky Sports, "There's been lots of positives from this weekend, I've really felt on it. I honestly thought I was shooting for pole today. And so, it's kind of a bit of a shock. I'll take it on the chin, and keep trying."

Any hopes of a clean qualifying quickly dissipated. Given the tight confines of the street circuit, it's not unusual for yellow or red flags to wave, particularly when drivers are putting together their flying laps. With 11 minutes and 33 seconds to go in Q1, the session was red-flagged after Alex Albon clipped the wall. It came at a poor time for Piastri and Antonelli, both of whom hadn't set a time yet.

It's a blow for Williams, after Albon showed top 10 pace throughout all three practice sessions. The team still sits fifth in the standings, with a 24-point gap over Aston Martin. But the margins are razor-thin in the midfield.

The session was red-flagged again, five minutes later, as Nico Hulkenberg found the wall. The Sauber driver was able to make it back to the pits, but debris needed to be cleaned on the track. Piastri only just logged his flying lap before the red flag, landing him a provisional second and 0.018 seconds off Hamilton's time, who was fastest at that point. But Antonelli exceeded track limits, leaving him without a time in P20 with just under seven minutes left in the session.

"Kimi, you have tons of time, six and a half minutes," team principal Toto Wolff said over the radio to the rookie, "just need a clean lap."

And he managed to do so, setting a lap that initially landed him sixth but shuffled down to P10 as other drivers put together their final flying laps for Q1. Considering Russell was fourth in Q1, the performance suggests Mercedes has found a competitive pace at the Baku City Circuit.

The session ended with a red flag as both Alpines went off, resulting in a double Q1 knockout. Franco Colapinto, the rookie driver, had his car damaged when he crashed into the barriers at Turn 4, while Pierre Gasly experienced a big gust of wind but didn't hit anything.

The string of incidents throughout Q1 highlighted the unique challenges that make Baku one of the most unpredictable venues on the calendar. Track position is critical at Baku City Circuit, if Q1 is any indication. It's not just because of the stoppages from crashes or debris. Wind is a big factor, given how close the track is to the Caspian Sea, and the tall buildings can create a tunnel effect. Gasly's off moment (and FP3 earlier on Saturday) shows how sensitive these cars can be to the conditions.

Azerbaijan F1 mayhem sees Verstappen on pole, Sainz second and Piastri crash