Spaniard Alonso's 1 minute, 21.962 lap at Monza was the only sub 1.22 turn in the qualifying round gave pole honors to Ferrari while Button and his McLaren took second position with a 1:22.084.
Felipe Massa and Mark Webber were placed in the second row followed by fifth-place Lewis Hamilton, the overall leading driver in this year's Formula 1 season. Hamilton slid in his first run and was unable to make up the lost time.
The Italian Grand Prix on Sunday consists of 53 laps.
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