Then in the 12th, Norris singled with one out off Cody Eppley (0-2) and went to second on a sacrifice bunt by Jemile Weeks.
That brought up Crisp, who lofted the first pitch from Eppley into right field, scoring Norris without a throw and giving the A's their major league-leading 11th walk-off victory of the year.
Jerry Blevens (3-0) earned the victory with two scoreless relief frames as Oakland logged its first-ever four-game sweep of the Yankees and won for the ninth time in 10 games overall.
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