Both of Napoli's homers were two-run shots and Josh Hamilton finished 3-for-5 with five RBI, including a three-run blast, as Texas cruised to a win in the first contest of a two-game series.
C.J. Lewis (2-0) collected the victory with seven strong innings, yielding two runs on eight hits. He didn't issue a walk and struck out seven.
Boston ace Jon Lester (0-2) was lit up for seven runs on eight hits in two innings. His ERA in three 2012 starts jumped to 5.82.
Dustin Pedroia hit a first-inning, two-run homer for the Red Sox.