The Colorado Rockies are off to one of the best starts in team history but could have trouble keeping it going in San Francisco.
Having won five straight, Colorado (5-1) is close to matching the franchise-best 7-1 start from its 1995 "Blake Street Bombers" club that eventually earned the club's first playoff berth. This year's Rockies are doing some slugging of their own with major league bests of 13 homers and 39 runs in their first six games.
Dexter Fowler hit his fourth homer of the season and Wilin Rosario had his third in Sunday's 9-1 victory over visiting San Diego.
"Everybody in this clubhouse can do damage at the plate. Right now, we're trying to play smart, score runs, trying to take the lead early and get confidence for the pitchers," said outfielder Carlos Gonzalez, who was among the many Rockies that endured a team-worst 98 losses in 2012.
Bumgarner (1-0, 0.00 ERA) was on the mound in four of those defeats and is 5-1 with a 1.75 ERA over his last nine games against Colorado. He's 2-1 with a 1.13 ERA in five all-time starts against the Rockies at AT&T Park, and had the majors' seventh-best home ERA last season at 2.38.
This will be his first start of the season in San Francisco after giving up two hits over eight innings in Tuesday's 3-0 victory at the Los Angeles Dodgers. The left-hander threw 76 of his 101 pitches for strikes.
"That's probably the best stuff I've had in a long time, which is odd because things don't work out too good in the first start of the year. Really, the first month of the year has usually been kind of tough to get it going. But it feels good to get started on a good note," said Bumgarner, whose career April ERA of 3.55 is his worst for any month.
With his help, the Giants' rotation gave up zero earned runs in the first four games but it's allowed a combined 14 in back-to-back defeats to visiting St. Louis over the weekend. Matt Cain was tagged for nine runs - all in the fourth inning - in a 14-3 drubbing Sunday.
Jorge De La Rosa (0-0, 8.31) will try to help send San Francisco (3-3) to another loss while reversing his recent struggles against the Giants. The left-hander is 1-3 with a 5.16 ERA in his last four matchups and gave up six runs over 3 2-3 innings in his only meeting last season, a 9-2 loss in San Francisco on Sept. 20.
The Giants, though, haven't done much hitting this season, totaling 15 runs and four homers while batting .224.
De La Rosa allowed four runs, five hits and three walks over 4 1-3 innings in his season debut, an 8-4 win in Milwaukee on Tuesday.
The Rockies haven't won six straight since a seven-game streak April 9-15, 2011, but they've lost six in a row in San Francisco. Colorado has also dropped 21 of 26 overall matchups.