How risky is drafting a high school catcher?

Greg Rosenstein of ESPN (Insider-only) discusses why high school catchers don't always make the best draft targets. This is, of course, relevant to the Pirates, who have repeatedly been connected to Washington high school catcher Reese McGuire with the No. 9 overall pick in the draft tomorrow.

"High school catchers don’t make the big leagues," a National League West scout said this week.

Of the 63 starting or backup catchers, roughly 20 percent were drafted out of the prep ranks at that position. You can count on your hands the amount that eventually made it out of the minors in the past decade.

High school catchers do sometimes make the big leagues, obviously -- Joe Mauer and Brian McCann are two obvious examples. But as a group, their performance is hard to project.

Rosenstein quotes a scout who says one problem is that high school catchers frequently don't develop the strength necessary to handle the position at the big-league level. Whether a high school catcher will develop the physical qualities required of the position is hard to project. The scout also says that conversions to catcher may tend to produce better results. Russell Martin's career path is instructive here -- he was drafted in 2002, then spent a year playing third base in the minors before switching to the catcher position in 2003. (You can read more about that here.)

Also, the mental and physical strain of catching in the minors may cause a player to fall behind in other ways. Neil Walker, who came up as a catcher, once said that he sometimes would give up on at-bats later in minor-league games because he was tired from having caught the whole game.

If the Pirates draft McGuire, then, they need to have a lot of confidence in McGuire's defensive skills, or they need to like his bat enough to be think it will also play at another position, or both. McGuire is well-regarded as a hitter, and he'll certainly be a first-round pick whether or not the Pirates take him, but the fact that he's a high school catcher means that the Pirates should proceed with caution.