Ian Kinsler and Nelson Cruz also homered for the Rangers, who are one game ahead of Detroit for the second-best mark in the American League and home- field advantage in the first round of the playoffs. The Tigers beat Cleveland Tuesday.
Since Texas doesn't hold the tiebreaker against the Tigers, the Rangers need either a win Wednesday or a Detroit loss to host a Division Series contest Friday against either Boston or Tampa Bay.
"We've been playing good baseball all year, especially down the stretch," Rangers manager Ron Washington said. "We know if we win tomorrow, our next game will be in Texas."
Colby Lewis (14-10) allowed three hits and a pair of runs over six innings for the AL West champions, who have won five in a row.
"Colby has a lot of pitches and he throws strikes. He kept us off balance tonight," Angels catcher Hank Conger said.
The 95 wins by the Rangers ties the most in club history. They had the same amount in 1999.
Tyler Chatwood (6-11), a replacement starter for Ervin Santana, was lifted after just 2 2/3 innings in which he gave up seven hits and four runs.
The Angels, who were eliminated from postseason contention Monday, took the early lead on Bobby Abreu's sacrifice fly in the first.
It all fell apart for Chatwood in the third. Kinsler homered to left with one out. After Elvis Andrus walked and Josh Hamilton singled, Michael Young and Beltre had back-to-back RBI base hits. Cruz's run-scoring single later in the frame made it 4-1.
Peter Bourjos tripled in Andrew Romine in the bottom of the inning, but Hamilton's sac fly in the fourth and three straight homers to start the fifth against Jerome Williams - by Beltre, Napoli and Cruz - extended the margin to 8-2.
Napoli blasted a two-run homer to left-center in the seventh off Trevor Bell before the Angels scored on a double-play grounder in the bottom portion.
The five homers by Texas ties a season-high...Lewis won his final three decisions of the season...This was Napoli's sixth career multi-homer game...Chatwood dropped his last five decisions. He's 0-3 lifetime against the Rangers...Texas is 39-17 vs. the AL West...Angels second baseman Howie Kendrick left the game after injuring his hand...Angels outfielder Jeremy Moore recorded his first MLB hit with a single in the seventh inning.
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