VIDEO: Altuve's walk-off homer hands Red Sox 8th straight loss

One of the only knocks on Jose Altuve is his lack of power, but the reigning batting champion is flexing his muscles in 2015.

The Houston second baseman launched his first career walk-off homer - a solo shot in the bottom of the ninth inning Thursday off Boston Red Sox reliever Craig Breslow - to propel the Astros to a 5-4 victory.

(Courtesy: MLB.com)

Altuve finished 4-for-5 with two runs scored and now has nine homers on the campaign. His previous season-high was seven a year ago.

The Astros completed a three-game sweep of the Red Sox and are riding a four-game winning streak into their weekend series with the Kansas City Royals, while the Red Sox have now dropped eight straight.