SAN DIEGO -- The streaking Houston Astros slugged three home runs for the second consecutive night, and they beat the San Diego Padres 14-3 Tuesday at Petco Park.

Houston got home runs from left fielder Evan Gattis, right fielder George Springer and first baseman Chris Carter while winning its fifth straight. Springer tied his career high with five RBIs.

The reeling Padres lost for the sixth time in seven contests.

Astros second baseman Jose Altuve had four hits, raised his average to .348 and ran his hitting streak to seven games.

Houston posted season highs in runs and hits (17).

Astros starter Roberto Hernandez (1-2) pitched six innings, allowing three runs on six hits and a walk with six strikeouts.

Hernandez, who won a roster spot out of spring training, helped the AL West-leading Astros to their ninth win in 11 road games, the best road start in franchise history. Houston also clinched its fourth consecutive series win and will seek its second straight road sweep Wednesday.

Padres right-hander Tyson Ross (1-2) went five innings and was charged with four runs on five hits. He struck out nine but walked two and hit a batter.

Springer smacked a two-run homer off Odrisamer Despaigne in the seventh to give the Astros an 8-3 lead. Third baseman Luis Valbuena was aboard after being hit by a pitch for the second time in the game.

The Astros added to the margin in the eighth with Springer's two-RBI single; then scored four more in the ninth.

Left fielder Justin Upton opened the sixth with his sixth homer of the season, pulling the Padres to within 6-3.

First baseman Chris Carter's home run in the sixth pushed the Astros to a 6-2 lead.

Center fielder Wil Myers' home run in the fifth brought the Padres to within 4-2. Myers' fourth homer of the season, which went over the Padres' bullpen, went 445 feet.

Houston tacked on another run in the fifth when loading the bases with no outs. Springer collected an RBI on a fielder's choice for a 4-1 advantage.

Catcher Derek Norris got in scoring position with two outs for the Padres in the fourth, thanks to his single and a groundout. But shortstop Marwin Gonzalez made a nice play on third baseman Will Middlebrooks' soft liner in short center field to end the threat.

The Astros increased their cushion to 3-1 in the fourth on Carter's run-scoring single, which extended his hitting streak to seven games. Carter drove in center fielder Colby Rasmus after he singled and stole second.

The Padres cut the Astros' edge to 2-1 in the first as second baseman Yangervis Solarte, with the first of his two hits, chased home Myers. Myers got aboard on a bunt single and stole second base.

The Astros struck quickly in the first as Gattis hit a two-run homer after Valbuena reached on a single. Gattis' second home run on the season ricocheted off Myers' glove in front of the center field fence before going over for a 2-0 Houston lead.

NOTES: Astros SS Jed Lowrie was placed on the disabled list and will undergo surgery to repair a torn right thumb ligament. He injured it Monday in the series opener on a slide at the plate. Houston called up SS Jonathan Villar from Triple-A Fresno. ... LF Evan Gattis was in the lineup after starting 16 of the Astros' 18 games at American League parks at DH. ... Astros manager A.J. Hinch hasn't decided on Friday's starter against the Seattle Mariners. ... Padres RHP Josh Johnson, a two-time All-Star, threw 40 pitches in a simulated game. He continues to make progress from his second Tommy John surgery. ... Struggling Padres 2B Jedd Gyorko will start Wednesday against Astros LHP Dallas Keuchel. RHP Andrew Cashner will start for San Diego.