Lewis Hamilton could not believe how far he has come after recording the 100th pole position of his career at the Spanish Grand Prix.
The seven-time world champion emerged triumphant from a three-way qualifying battle with Max Verstappen and Mercedes team-mate Valtteri Bottas.
Hamilton ended up 0.036 seconds clear of Verstappen, with Bottas just 0.132s behind in third as none of the drivers improved in their second runs of an entertaining Q3 session.
Charles Leclerc took an impressive fourth for Ferrari, with Sergio Perez having to settle for eighth in the second Red Bull after spinning in his first run of the top-10 shoot-out.
Hamilton was overjoyed to come out on top as he continues to pull out impressive results despite the improved pace of rivals Red Bull in 2021.
"I will always remember that one," said Hamilton, who leads the drivers' standings by eight points.
"Wow, I can't believe we are at 100 and it's really down to the men and women back at the factory who are continuously raising the bar and just never giving up.
"The support I have, it's been a dream for me to work with these guys. The journey we have been on, it has been immense.
"Who would have thought at the end of 2012 when we made the decision to partner, we'd be qualifying at 100? I feel very humble and grateful – and I am ecstatic it's like my first!"
Hamilton revealed some changes to the car ahead of qualifying had him worried throughout much of Saturday.
The Briton added: "We have been strong all weekend and I made some changes - I had a bit of anxiety about the changes.
"For qualifying, you're always trying to make the car better, but it is a bit of a gamble because you have to keep the race in mind also.
"We made the change and immediately I thought, 'This is the wrong one'. It was my call at the end, but it was really hard.
"The changes that we made, I had so much understeer, the car was being lazy and wouldn't turn corners the way I wanted. I was making small adjustments to get the car to turn.
"So that's why I was behind the whole qualifying. I was making small tweaks here and there to make pace but the first lap [in Q3] was the best lap of the session - which was great."
Verstappen – who topped a Q2 session that saw Sebastian Vettel, Lance Stroll and Pierre Gasly among the eliminated drivers - was right there with Hamilton as a thrilling title battle continued.
"It was good, to be that close, we can be happy with that," said Verstappen. "I struggled in Q1 but we sorted out the balance in Q2 which was good.
"Q3 both laps were pretty decent, the second run was a little worse. It is quite gusty.
"Second for us is very good. We know they are hard to beat around here.
"To be that close, we can be happy with that – it is a long run down to turn one on Sunday, we have to make sure we get a good start and then see if the pace is there."
Bottas, who had made Hamilton wait for his 100th pole by topping the timesheet in Portugal, was competitive once again.
"That was close," he said. "Definitely was in the battle for the pole and I think the first runs in Q3 were faster ones.
"I had snap at the apex at turn 10 and lost a tenth or so, and that's the margins of the pole. With a strong package, it's going to be a good fight between us and Red Bull on Sunday no doubt."
The closest driver to Hamilton in terms of F1 pole positions is Michael Schumacher on 68.
Hamilton now has only 29 fewer poles than the rest of the current F1 drivers combined (129), while he is seeking a sixth race win in Barcelona that would the tie record held by Schumacher.
If he does it, the Mercedes star will lead the win rankings in 16 of the 32 tracks he has raced on during his illustrious career.
Verstappen took the first of his 11 career victories in Barcelona as an 18-year-old back in 2016, becoming the youngest race winner in F1 history, though Hamilton has won each of the four editions to be held since.
PROVISIONAL CLASSIFICATION
1. Lewis Hamilton (Mercedes) 1:16.741
2. Max Verstappen (Red Bull) +0.036s
3. Valtteri Bottas (Mercedes) +0.132s
4. Charles Leclerc (Ferrari) +0.769s
5. Esteban Ocon (Alpine) +0.839s
6. Carlos Sainz (Ferrari) +0.879s
7. Daniel Ricciardo (McLaren) +0.881s
8. Sergio Perez (Red Bull) +0.960s
9. Lando Norris (McLaren) +1.269s
10. Fernando Alonso (Alpine) +1.406s