The Mariners broke the record set last year by Baltimore. Seattle had equalled the Orioles' 1996 mark when Ken Griffey Jnr hit his 55th in Oakland on Monday. With his three-run drive in the first off Allen Watson, Buhner became the 10th player to reach 40 in three consecutive seasons, the first since Frank Howard in 1968-70. Buhner hit a career-best 44 homers last season after getting 40 in 1995.
The Cleveland Indians clinched their third successive American League Central Division title with a stunning comeback from a seven-run deficit, defeating the New York Yankees 10-9 in the bottom of the ninth inning. Trailing 9-2 in the sixth, the Indians scored four in the sixth, two in the eighth and two in the ninth inning.
Twenty minutes later, the second-placed Chicago White Sox lost, handing Cleveland the crown. The Indians will face the AL wild card - probably the Yankees -in next week's Division Series.
In Toronto, the Orioles moved closer to clinching the American League East with a 3-2 victory over the Blue Jays. Nerio Rodriguez, making his second start of the season, allowed two runs and two hits in 5 1/3 innings. Arthur Rhodes and Armando Benitez combined to allow one hit in 2 2/3 innings and Randy Myers struck out one in a perfect ninth for his 44th save in 45 opportunities.
In Chicago, Brent Brede snapped a fifth-inning tie with a two-run homer as the Minnesota Twins earned a 5-3 victory over the White Sox, who were officially eliminated from the play-off race. Denny Hocking walked to lead off the fifth and one out later, Brede hit his third homer of the season and a 5-3 lead.
"Cleveland played their best ball down the stretch and they earned their division win," the White Sox first baseman, Frank Thomas, said.
He provided Chicago's offense with a three-run homer in the third inning, his 34th. That was his only hit, but his .352 average still leads the AL.