The Diamondbacks are about to be loaded with young pitching.

The organization already has Ian Kennedy (26) and Daniel Hudson (24) pitching like above-average starters in Arizona. Jarrod Parker is making his way back from Tommy John surgery, lefthander Tyler Skaggs may have already passed him with his stellar showing for high Class A Visalia and lefty Pat Corbin has been solid for Double-A Mobile. Add 2011 first-rounders Trevor Bauer and Archie Bradley to the mix and the Diamondbacks will have a collection of young arms that will stack up favorably against any organization.

While Hudson was the key piece the Diamondbacks received in the 2010 deal that sent Edwin Jackson to the White Sox, Arizona also got lefty David Holmberg, a second-round pick in 2009 who has been terrific in his last four starts.

Holmberg, 19, struck out 10, didn't walk anyone and allowed just two hits in seven shutout innings yesterday, the fourth straight start in which he hasn't allowed a run. He's working on a scoreless inning streak that stretches 27 innings, which has lowered his ERA to 2.61 in 76 innings with 74 strikeouts and 13 walks.

• Cardinals righthander Shelby Miller showed why he's in the conversation as the top pitching prospect in the minors yesterday, working with a low-90s fastball that he ran into the mid-90s to shut out Double-A Arkansas for eight innings. Miller, 20, walked two and struck out eight to lower his Texas League ERA to 1.35 through three starts.

• It looks like Michael Taylor might be back. At the very least, his .302/.368/.509 line through 26 games for Triple-A Sacramento is an encouraging sign for the Athletics' 25-year-old corner outfielder. Taylor chipped in three hits yesterday for the River Cats, including his sixth home run of 2011.

• Taylor's teammate, 25-year-old Josh Donaldson, also picked up three hits, including two home runs and a double to bump his averages up to .252/.316/.439 through 54 games. Donaldson, who has split time between catcher and third base this year, struggled in April but since May 1 he has hit .285/.335/.490 in 164 plate appearances.

• Royals catcher Salvador Perez had arguably his best game of the year yesterday for Double-A Northwest Arkansas, going 3-for-4 with a home run and a double. Perez has a solid swing and makes a lot of contact, but he's still learning to corral his free-swinging approach, as he's drawn just nine walks all season and hitting just .259/.301/.373 through 47 games.

• In another farm system, Arodys Vizcaino would be the top pitching prospect. While righthander Julio Teheran is closer to making an impact in Atlanta, Vizcaino has flashed a fastball and a curveball that each grade out anywhere from 60 to 70 on the 20-80 scouting scale. Yesterday the 20-year-old righthander struck out nine in 7 2/3 innings for Double-A Mississippi, holding Jacksonville to one run, one walk and five hits.

• Reds low class A righthander Daniel Corcino threw six more shutout innings yesterday, the fourth time in his last seven starts in which he hasn't allowed a run. Corcino, 20, is pushing for a promotion to high Class A Bakersfield with an ERA of 2.53 and an 81-14 K-BB mark in 67 2/3 innings.