WASHINGTON - Matt Howard's free throw with one second left lifted Butler to a stunning 71-70 upset of No. 1 seed Pittsburgh in the third round of the NCAA tournament on Saturday.

After Butler took a 70-69 lead on Andrew Smith's basket with 2.1 seconds left, Pittsburgh's Gilbert Brown was inexplicably fouled near halfcourt by Butler's Shelvin Mack with 1.4 seconds to go. Brown made the first free throw and missed the second.

Howard was fouled as he grabbed the rebound with .9 seconds left. He made the first free throw and purposely missed the second to send Butler into the Sweet 16 and a meeting with Wisconsin in the Southeast Regional in New Orleans on Thursday.

Mack scored 30 points and was 7 for 12 from 3-point range for eighth-seeded Butler (25-9), which lost to Duke in the NCAA title game last year. Howard scored 16.

Brown scored 24 points for the Panthers (28-6), who won the Big East regular season title. Ashton Gibbs, who averaged 17 points, finished with 11.

The Panthers shot 56.5 percent from the field and outrebounded the Bulldogs 31-21.

Howard's buzzer-beater gave Butler a 60-58 victory over Old Dominion in the second round Thursday.