While we documented a couple days ago how several Padres hitting prospects are off to fantastic starts, righthander Keyvius Sampson has been San Diego's biggest story on the mound.

Sampson, 20, turned in another dominant performance Wednesday for low Class A Fort Wayne, tossing five shutout innings and allowing only one hit against Lake County. The Captains owned the Midwest League's most productive offense, leading the league in runs and home runs and ranking second in average. Then they ran into Sampson, who did issue four walks but also struck out seven.

Sampson picked up his third win in four starts and improved to 3-1, 1.29 in 21 innings on the season. He's allowed just six hits on the season, and righthanded hitters are an astounding 1-for-32 against him. His .091 opponents average overall is tied for the minor league lead with Reds high Class A righthander Josh Ravin, who's pitched 3 2/3 fewer innings. Sampson's seven strikeouts Tuesday put him in the Midwest League lead with 28 on the year.

“He knows he has good stuff," Fort Wayne manager Shawn Wooten told the Fort Wayne News-Sentinel. "He has two pitches he can throw at any time for strikes (and a) third pitch, his breaking ball, that can keep guys off balance.”

• The cold weather of the upper Midwest hasn't slowed Twins outfielder Oswaldo Arcia much yet. Arcia got off to one of the Midwest League's hottest starts until a three-game hitless skid last week dropped his average from .342 to .283. The 19-year-old has bounced back quickly though, going 2-for-4 Monday and then 4-for-4 with two home runs yesterday for low Class A Beloit, his third career multi-homer game. Elbow and shoulder problems have continued to prevent Arcia from playing in the field this year, but they haven't limited him at the plate, as he's hitting .352/.429/.667 in 54 at-bats as a full-time DH.

• The high Class A Florida State League is supposed to be a pitcher's league, but you couldn't tell that from Phillies righthander Trevor May's numbers—until yesterday. May had allowed 12 earned runs in 14 innings over his first three starts for Clearwater, coming on the heels of a 2010 season in which he battled mechanical problems and went just 5-5, 5.01 as a Thresher before a demotion. May got on track Tuesday, tossing a seven-inning complete game to beat Tampa. The 21-year-old struck out six while permitting only one run on four hits with no walks, improving to 1-2, 5.57 in 21 innings. The seven innings matched May's longest walk-free outing of his career, spanning 51 appearances since he was a fourth-round pick in 2008.

• Rockies outfielder Kyle Parker has made a smooth transition to low Class A. The former Clemson quarterback went 3-for-4 with two doubles and an RBI last night, his seventh multi-hit game in 13 outings this season. The 26th overall pick in last year's draft, Parker took over the lead in the South Atlantic League batting race and moved into a tie for fifth in the minors by taking his line to .435/.491/.652 in 46 at-bats. While Parker's considerable power potential hasn't fully come to fruition yet—he's hit only one home run—he is making hard contact and his seven doubles tie him for second in the SAL.

• Twins righthander Kyle Gibson was hit hard in his first start of the year for Triple-A Rochester, but he's righted the ship quickly. Gibson struck out eight over six innings against Buffalo on Tuesday while giving up one run on four hits. This start was Gibson's third straight quality outing since he lasted just three innings on April 9 while giving up three runs on seven hits. Since then, Gibson's allowed just four runs on 10 hits in 17 innings with 17 strikeouts. The only thing missing has been run support, as he took the loss Tuesday and is still looking for his first win, sporting an 0-1, 3.15 record.