Holmberg runs scoreless streak to 34

It's hard to remember the last time David Holmberg allowed a runner to score this season. Literally.

Holmberg, a D-backs prospect in the Class A Midwest League, ran his scoreless-inning streak to 34 on Tuesday, holding West Michigan to just one hit over seven innings in South Bend's 7-1 win at Fifth Third Ballpark.

"I had a lot of pitches working for me today," Holmberg said. "I had the curveball and slider going, and my command of fastball was there all day. I missed a few change-ups here and there and got away with couple mistakes. Fortunately, I was able to record a lot of outs."

The left-hander from Port Charlotte, Fla., has posted a string of zeros in each of his last five starts for the Silver Hawks. The last run he allowed came back on May 22, in the fourth inning of his outing against Dayton. He retired the final three batters after allowing the run that frame, beginning a stretch of domination that could enter its third month in his next start.

"It's just one of those things that came about," he said. "From here on out, I'm just going to keep doing the same things I've been doing, using all my pitches to keep the hitters off balance. If [the streak] keeps on, it keeps on. If I lose it, it's not a big deal, as long as we keep getting 'W's."

The White Sox's second-round pick in 2009 struck out seven and did not walk a batter for the fourth straight start, improving to 8-3 with a 2.39 ERA. He has the second-longest scoreless streak in the Midwest League since 2005, as well as the second-longest run in the Minors this season.

"I didn't have one of those eureka moments," he said. "It's just a matter of putting your nose to the grindstone, putting your time in the bullpen and working with the pitching coach. I'm putting everything I have into every game and it seems to be working."

West Michigan's lone hit came in the third Jeff Rowland grounded a two-out single up the middle. Nick Castellanos reached on a fielding error by third baseman Matt Helm in the fifth, the only other batter to reach base against Holmberg.

The 19-year-old got the streak going with five innings on May 29, when he held Dayton to three hits. He followed that with his first career complete-game shutout, limiting Quad Cities to a pair of hits June 3. He shut down Burlington over six innings June 9 and then struck out 10 batters while only giving up a pair of hits over seven frames against Lansing on June 15.

"It's not like every outing all of my pitches are there. But for the most part, if something's not there, for instance the curveball, then I'll go with the pitches that are working and use those," he said. "And then later, I'll put my time in and with the pitch that's not working."

He's 8-0 with a 1.77 ERA in his last 10 starts and has credited his change-up as one of the biggest aspects of his success this year.

"I've been using that a lot, and my catchers have been calling it a lot. I've been keeping it down, and it's good to use that change of speeds in a tight situation," he said. "To get a ground ball or a swing-and-miss when you need it is a great help."

South Bend gave its starter some runs to work with in the third when Roberto Ortiz hit an RBI double, Michael Freeman had a run-scoring single, Yazy Arbelo lifted a sacrifice fly and Raywilly Gomez knocked home Zach Walters.

"Our offense hit well. They were seeing the ball well," Holmberg said of his lineup, which tacked on three more runs in the ninth. "It might have been just one of those days for [West Michigan], but we'll take it. It's another 'W' for us."

Holmberg, acquired by Arizona with pitcher Dan Hudson from Chicago for Edwin Jackson on July 30, 2010, went 2-5 with a 4.17 ERA in 15 starts last year between short-season Idaho Falls and Missoula. He appeared in 14 games with Rookie-level Bristol in 2009.

Now comfortable in the D-backs' system, the lefty said he's thought about taking the next step.

"It's something that comes through my head every once while, but it's not a big deal," he said of moving up. "I'm going to be pitching here like I'm going to be pitching anywhere else. Every time I go out, I'm doing the same thing, trying to locate my pitches and just keep on improving."