His swing is still sometimes raw, and he's made six errors in his transition to shortstop after playing second base last year. But seemingly every night, low Class A Dayton's Billy Hamilton (Reds) demonstrates once again how he may be the fastest player in baseball. This week he hit .391/.533/.609 (9-for-23), with eight runs scored, two doubles, an inside-the-park home run (in which he was timed at under 15 seconds around the bases), seven walks and six steals in nine tries. But the 20-year-old's most impressive feat of the week may have been when he scored from third on a comebacker to the mound . . . When your fastball tops out at 90 mph, you need to have plenty of savvy, not to mention some quality secondary offerings, to make it work. That's the case for Mets LHP Mark Cohoon, who's allowed just one earned run in 19 innings this season for Double-A Binghamton. In his only start this week, the 23-year-old threw seven innings without allowing an earned run (he did give up two unearned) to lower his ERA to 0.47. He struck out 11, a career high, didn't walk anybody and gave up just five hits . . . A shortstop by trade, Orioles prospect Jonathan Schoop has moved over to third base with low Class A Delmarva in deference to Manny Machado. Schoop, 19, hasn't taken a back seat to anyone at the plate though, as he's riding a nine-game hitting streak and hit .419/.500/.677 (13-for-31) with two homers and two doubles this week . . . Because he's on a relatively limited 75-85 pitch limit, Royals LHP Danny Duffy has yet to work more than five innings in any of his first three starts. But Duffy, 22, has been outstanding in those limited stints for Triple-A Omaha. This week Duffy threw nine scoreless innings in two starts, allowing just six hits while walking three and striking out 12 . . . As a second-round pick last year out of Indiana State with a fastball that consistently gets into the mid-90s, White Sox RHP Jacob Petricka shouldn't face too many problems in low Class A. He's come as advertised so far pitching with Kannapolis, where he's allowed one run in 11 innings over his last two starts. Petricka, 22, now has an ERA of 0.53 and a 22-4 K-BB mark in 17 innings . . . Cubs CF Jae-Hoon Ha has caught scouts' eyes in the Florida State League with eye-popping numbers to start the season. He is hitting .403/.406/.645 through 14 games with a pair of home runs. He has not drawn a walk yet and is only 2-for-7 on stolen base attempts, but manager Buddy Bailey is pleased with the 20-year old's aggressive approach. "He's got one gait and it's always aggressive," Bailey said. "To me, it's the perfect thing for a young player. Players learn when they're aggressive." . . . Blue Jays LF Eric Thames made the most of a seven-game home stand for Las Vegas. Thames snapped out of a 2-for-14 skid by going 16-for-28 with eight extra-base hits this week. The 24-year old is hitting .417/.500/.700 with 10 walks and 13 strikeouts this season. He also has cut down on his strikeouts after whiffing 121 times in 130 games at Double-A New Hampshire last year.