Greg Halman was signed by the Mariners out of the Netherlands in 2004. A superb athlete, he was extremely raw when signed, but has made some progress refining his baseball skills and making those tools meaingful. He's got plus actuality or potential in all traditional Five Tool categories: hitting, hitting for power, running, throwing, fielding. But what about the Seven Skills?
Halman began 2007 at Wisconsin in the Midwest League and was terrible, hitting .182/.234/.273 with an 8/77 BB/K ratio in 187 at-bats. He was so overmatched that they sent him to Everett in the Northwest League in June to start over. He did much better at Everett, .307/.371/.597 with 16 homers and 16 walks, though his strikeout rate remained scary-high with 85 whiffs in 238 at-bats. I gave him a Grade C+ in the book this year, noting that his potential was immense but that the risk factor was huge.
The Mariners sent Halman to High Desert in the California League this spring, a bold move considering how horrible he was at a lower level last year, plus at age 20 he would be one of the youngest players in the Cal League. His numbers at High Desert are most interesting: .268/.320/.572 with 19 homers, 23 steals in 24 attempts, 16 walks, and 76 strikeouts in 257 at-bats through 67 games. Terrific power and speed, with bad plate discipline...although not nearly as bad as the first half of 2007.
Of course, hitting conditions in the Cal League are easier than in the Midwest League, even if the experience and talent level of the pitchers is generally better. Nevertheless, he ranks ninth in the league in OPS, huge improvement compared to last year. You might think this is some sort of High Desert mirage, but it isn't: his home numbers are .269/.338/.567, his road numbers .268/.300/.577, just a 30 point difference in OPS all traced to a higher walk rate at home. To me, it looks like the improvement is real, in terms of his power and speed playing in games.
Better production or no, the BB/K/AB ratio is still weak and points to contact/discipline problems against better pitching. Personally I think Halman should stay in the Cal League at least another month, but the Mariners apparently disagree: he popped up on the Double-A West Tennessee roster yesterday, and we will soon get to see what happens when he's challanged with real breaking balls.
At this point, Halman is a real wild card...a guy who could become a superstar if he develops even average pitch recognition and plate discipline, a mediocre player if he makes some progress but not quite enough, or a total washout against advanced pitching if he never gets the zone down. The Mariners like to push their prospects and it will be fascinating to see how it works, or doesn't work, with Halman.