LOS ANGELES — Manny Ramirez hit his first two home runs of the season — and dropped a flyball for his first error — and Andre Ethier also homered twice as the Los Angeles Dodgers extended their winning streak to seven games with a 9-5 victory over the Colorado Rockies today.

Ethier drove in four runs while batting second for the first time this season. Manager Joe Torre shuffled the lineup to give shortstop Rafael Furcal, third baseman Casey Blake and catcher Russell Martin the day off after Friday night's come-from-behind win.

Chad Billingsley (3-0) allowed three runs and four hits over six innings with six strikeouts and three walks. The right-hander was staked to a 5-0 lead before the Rockies got on the board in the sixth when Brad Hawpe hit a two-run triple past a diving Ramirez in the left-field corner and Ian Stewart had a sacrifice fly.

The Dodgers increased their lead to 9-3 with four runs in the seventh, the first on Ethier's second homer of the game and fourth of the season. Kemp added an RBI single that extended his season-opening hitting streak to 11 games, Juan Castro hit a sacrifice fly and Will Ohman had an RBI single.

Aaron Cook (0-1) gave up five runs and eight hits over four innings, allowing three home runs. The right-hander, who beat the Dodgers twice last year, surrendered three home runs. Cook has allowed five homers in his first 12 1-3 innings this season, after giving up just 13 in 211 1-3 innings last year.

Both of Ramirez's home runs came with the bases empty and increased his career total to 529, five behind Jimmie Foxx for 16th place all-time and seven shy of Mickey Mantle's total.

The 12-time All-Star, who signed a two-year, $45 million deal on March 4 after weeks of protracted negotiations, snapped his season-opening drought of 11 games and 36 at-bats without a home run. The longest stretch the 17-year veteran has gone from the start of the season before hitting his first homer was in 2006 (16 games, 55 at-bats). He also came out of that drought with a pair of homers against Toronto.

The multihomer game was the 54th for Ramirez, tying Frank Robinson for ninth place in that category. The two RBIs tied Honus Wagner for 19th place on the career list at 1,732.

Ramirez drove 3-2 pitch to left-center with two outs in the first to open the scoring. In the third, he deposited Cook's 1-0 delivery into the lower seats in the left field corner.

Ethier increased the margin to 5-0 in the fourth with a three-run shot, driving a 3-1 pitch deep into the right field pavilion. He and Ramirez became the first pair of Dodgers to each homer twice in the same game since Aug. 19, 2004, when Shawn Green and Adrian Beltre did it in a loss to Atlanta.

Ramirez's error on Hawpe's routine fly followed a leadoff walk to Garrett Atkins. Both runners advanced on Stewart's groundout, but Billingsley got Ramirez off the hook by striking out Troy Tulowitzki and retiring Yorvit Torrealba on a fly to center.