Lewis Hamilton took pole in the first-ever Tuscan Grand Pix qualifying after edging Mercedes teammate Valtteri Bottas.
Bottas swept the practices and was fastest in Q1, but Hamilton took advantage when it mattered most and beat his teammate in Q2 - the first time he had topped a session this week - and maintained his lead in Q3.
"This track is phenomenal," said Hamilton. "It's a really really challenging circuit, and Valtteri was quicker than me all through yesterday, this morning, and even in Q1. I've been working so hard in the background to try and improve. The team did such a great job and I finally got the lap I needed."
Bottas felt pole was 'definitely' taken away from him as his last chance at beating Hamilton's lap was upended by a yellow flag.
"I still had more time in there. Run one was okay, but not perfect. I was looking forward to the last lap but I didn't get the opportunity.
"It's disappointing because the speed has been good all weekend."
A Mercedes double at the top will surprise no one but there were shocks further down the rankings as AlphaTauri's Pierre Gasly was knocked out of Q1, just one week after winning his maiden Grand Prix in Monza.
Ferrari's Sebastian Vettel qualified at his expense by the barest of margins, but was knocked out himself in Q2 after finishing 14th.
But Charles Leclerc - Ferrari team leader since Vettel announced his decision to join Aston Martin - did help Ferrari into the top five, finishing fifth.
Red Bull's Max Verstappen and Alex Albon ran Mercedes close in Q1, but were unable to keep pace from then on and will line up third and fourth respectively.
This the eighth-straight front-row lockout for Mercedes, but at just 0.3s behind that is the closest Verstappen has come to breaking the hegemony.
1. Lewis Hamilton (Mercedes).1:15.144s
2. Valtteri Bottas. Mercedes. 1:15.203s
3. Max Verstappen. Red Bull. 1:15.471s
4. Alexander Albon. Red Bull. 1:15.914s
5. Charles Leclerc. Ferrari. 1:16.270s
6. Sergio Pérez. Racing Point. 1:16.311s
7. Lance Stroll. Racing Point. 1:16.271s
8. Daniel Ricciardo. Renault. 1:16.243s
9. Carlos Sainz. McLaren. 1:16.522s
10. Esteban Ocon. Renault. 1:16.297s
11. Lando Norris. McLaren. 1:16.640s
12. Daniil Kvyat. AlphaTauri. 1:16.854s
13. Kimi Räikkönen. Alfa Romeo. 1:16.854s
14. Sebastian Vettel. Ferrari. 1:16.858s
15. Romain Grosjean. Haas. 1:17.069s
16. Pierre Gasly. AlphaTauri. 1:17.125s
17. Antonio Giovinazzi. Alfa Romeo. 1:17.220s
18. George Russell. Williams. 1:17.232s
19. Nicholas Latifi. Williams. 1:17.320s
20. Kevin Magnussen. Haas. 1:17.348s