Jackson was nicknamed "Mr. October" for his clutch hitting in the postseason with the Athletics and the Yankees. He helped Oakland win five consecutive American League West divisional pennants, three consecutive American League pennants and two consecutive World Series titles (he did not play in the 1972 World Series due to injury), from 1971 to 1975. Jackson helped New York win four American League East divisional pennants, three American League pennants and two consecutive World Series titles, from 1977 to 1981. He also helped the California Angels win two AL West divisional pennants in 1982 and 1986. Jackson is perhaps best remembered for hitting three consecutive home runs at Yankee Stadium in the clinching game 6 of the 1977 World Series.

This Rawlings official Major League baseball has been signed in blue ballpoint pen by Jackson and includes a Mounted Memories hologram and COA.