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Matt Cain tries to keep heading in the right direction on Thursday night when he starts the opener of the San Francisco Giants' four- game series with the Colorado Rockies.

The former All-Star has won back-to-back starts since beginning the season 0-2 through six outings while shaving his earned run average from 6.49 to 5.04. Cain has done so by allowing just three runs over 15 1/3 innings in the two wins.

The right-hander has also struck out 12 batters over that time, fanning seven in eight innings of work in Friday's 8-2 win over Atlanta.

"We needed a lot of length in the game tonight and he did more than that. He gave us eight solid innings and threw a terrific game for us," Giants manager Bruce Bochy said.

Cain has also been helped by giving up just one homer over his win streak after yielding nine over his first six outings.

The 28-year-old won both of his starts last year versus the Rockies with a 1.76 ERA and is 15-7 against them lifetime with a 3.11 ERA in 28 meetings.

While Cain is hoping to round into form, the Giants may need to just get back to basics. They were recently swept in a two-game series by the Toronto Blue Jays, undone in both games by mistake-plagued first innings.

After Pablo Sandoval and Angel Pagan committed errors in the first inning of a 10-6 loss on Tuesday, with the Blue Jays scoring six times in the frame, Pagan and Marco Scutaro were charged with errors in the opening inning of Wednesday's 11-3 setback.

The miscues helped fuel the Blue Jays' five-run first inning and led to starter Ryan Vogelsong lasting just two innings. He took the loss, charged with eight runs -- three earned -- on six hits.

"I can't think back to when we had two games, identical games, where we made mistakes there in the first inning. The big number there killed us, took us out of our game," Giants manager Bruce Bochy said.

Scutaro followed up a three-hit game the previous day with a single in the ninth inning to extend his hitting streak to 14 games. He is batting .482 over the run.

Scutaro is 2-for-7 lifetime versus Rockies right-hander Jhoulys Chacin, who gets the start tonight having followed up three straight winning starts with consecutive losses.

Chacin did deserve a better fate on Saturday versus St. Louis as he yielded two runs or fewer for the fifth time in his six starts. He was charged with eight hits and three walks over five innings of work, but was on the losing end of a 3-0 decision as the Cardinals' Adam Wainwright spun a two-hit shutout.

Chacin is 3-2 with a 2.70 ERA on the year and the 25-year-old has gone 3-4 lifetime versus the Giants with a 3.59 ERA in 10 games (9 starts).

Colorado has lost six of its past eight and dropped Wednesday's rubber match of a three-game set with the Chicago Cubs by a 6-3 margin.

Jon Garland surrendered seven hits and three runs over five frames for the Rockies, who failed to build on a 9-4 win Tuesday.

"I felt like he gave us a chance," Rockies manager Walt Weiss said of Garland. "He pitched well enough to keep us within striking distance and win that game."

Josh Rutledge had a pair of RBI singles and Reid Brignac smacked a pinch-hit homer in defeat.

The Giants swept a three-game set from the Rockies at home from April 8-10 and have won nine straight in the series.