ARLINGTON (Reuters) - Matt Downs belted a two-run homer in the top of the ninth to cap a stunning come-from-behind 5-3 victory for the Houston Astros over the Texas Rangers on Wednesday.

The win enabled the Astros to avoid a three-game sweep in the interleague series against their state rivals, as Houston took advantage of a poor showing from the Rangers bullpen after starter Colby Lewis had pitched brilliantly.

The right-hander was in fine form, allowing just three hits through seven scoreless innings but his good work was undone by reliever Dave Bush and closer Neftali Feliz, who gave up five runs between them over the last two frames.

"I'm sure his (Feliz) arm wasn't as live as it would have been on a fresh night because he threw 40 pitches last night," Downs told reporters.

Feliz entered the game with a 3-1 lead but gave up doubles to Carlos Lee and Chris Johnson, and a single to Jason Michaels to let Houston pull back one run.

A passed ball allowed Johnson to score and tie the game before Downs, pinch hitting for Clint Barmes, completed the comeback with his fifth home run of the season.

"We had the right guy in the right spot," Rangers manager Ron Washington said. "We're not going to make any excuses. We didn't get it done."

Texas scored a run in the first inning and Nelson Cruz extended the lead to 2-0 with a solo blast in the fifth inning.

The Rangers tagged on another run in the eighth and had winning pitcher Mark Melancon in trouble later in the inning but failed to capitalize when Yorvit Torrealba grounded out with the bases loaded.

(Reporting by Mike Mouat in Windsor, Ontario. Editing by John O'Brien)