The disappearing defensive prospects

As a minor-leaguer Adam Dunn once stole 20 bases, sending a warning up for still-growing Bryce Harper US Presswire, Icon

Adam Dunn is finally a designated hitter this year, an inevitability that would have occurred years ago had he played with American League teams who didn't have to worry about hiding his defensive inefficiencies at first base or a corner outfield slot. Dunn is hardly the first bat-only player to be worth big money, and he'll hardly be the last.

Many believe that New York Yankees catcher Jesus Montero is the best offensive prospect in baseball. But the chances of him holding on to that catcher label seem thin. He's well below-average at the position and will likely spend the majority of his big league career known for his bat only.

And then there is Bryce Harper. Sure, he's very athletic now, but he's also a 6-foot-3, 225-pound 18-year-old who is far from physical maturity. It's easy to forget that Dunn was once a similar talent. As a teenager, he was a potential Division I quarterback and was similar in size and athletic ability to Harper at a young age, when he was listed at 6-5, 235 in Low-A when in the 2000 season he (believe it or not) had more stolen bases (24) than home runs (16).

Beyond the size, there are also elite-level young hitters consistently moving down the defensive spectrum. Some, like eventual Pittsburgh Pirates first baseman Pedro Alvarez, lack athleticism, while others, like Milwaukee's Ryan Braun, just can't seem to find a knack at a position they have all of the tools to succeed at.

Is this new? Is defense overall in baseball declining, and if so, why? I spoke to a number of scouts, executives and industry insiders about the issue, and the opinions were wide-ranging.