Fernando Alonso admitted he was surprised to be able to keep pole position at Monza, after the Ferrari driver gave his team its first pole since 2008.
Alonso scored Ferrari's first pole since the Brazilian Grand Prix two years ago, ending the Italian squad's longest drought since the 1990s.
It was also the Spanish driver's first pole of the season, and Alonso admitted he was expecting someone to beat him in the dying moments of qualifying.
"It was a nice surprise," said Alonso, whose result meant his 19th pole in F1. "I stopped in parc ferme and by radio they told me we were keeping pole position but there were still a couple of guys doing laps, and Button had a pink in middle sector.
"I thought in the end someone would arrive on the last lap and we would be second or third by a some hundredths of a second.
"Today was different. We remained on pole position until the end - a nice surprise, a much better feeling."
Alonso, who is 41 points behind championship leader Lewis Hamilton said he felt no pressure to win tomorrow's race, but conceded it was vital to finish at least on the podium.
"Tomorrow we need a podium minimum to remain in the fight but there is not a big pressure," he said. "There is not a big stress about winning the race or the next races, but at the same time we know we cannot afford another DNF or another bad result.
"Let's be consistent, try to be on the podium minimum. If we can win the race great, we need consistency - something we didn't have so far in the championship. Tomorrow we have a good chance to put a strong result and see how our opponents go."
Team-mate Felipe Massa completed Ferrari's best qualifying of the year after securing third position.
The Brazilian was confident of a strong race.
"I think we have a good car," he said. "I am happy with the car for the race. Yesterday we did a good job, we improved massively the car and I think we should be very strong tomorrow and I am looking forward."