Prospects that broke your heart

In the All-Questions Answered thread earlier today, Minor League Ball community member Naropean posed the following question:

When I was growing up, Ruben Mateo of the Rangers broke my heart after he got hurt and never got close to realizing his potential. This was when I started paying attention to prospects. Was there any minor league prospect who similarly broke your heart as a young baseball fan? Or something similar?

That's a great question. As a prospect follower since the late 1970s, there have been a ton of guys like this for me, of course. Some of them should have been good but weren't, often due to injury. Some really weren't very good, but I liked them for one reason or another. Some names that pop up for me, in no particular order:

Ruben Mateo: Like Naropean, I really liked Mateo when he was coming up. The tools were impressive and it looked like he had the skills to make them work, but he suffered a catastrophic leg injury in 2000 and never looked the same on the field again. Maybe he would have failed anyway but the injury sure didn't help matters.

Mark Funderburk: Growing up as a Twins fan in the 1980s, I was excited when a minor league veteran named Mark Funderburk hit 34 homers in Double-A in 1985, was promoted to the majors and hit .314/.351/.529 in 70 at-bats down the stretch for the Twins that year. He never played in the majors again.

Calvin Pickering: Erstwhile Baltimore Orioles prospect with a devastating Triple-A power bat, like Funderburk he had a brief run of success in a big league trial (seven homers in a quick 35 games for the Royals in 2005) but kept getting hurt and didn't have the defensive value to hold a job if he went into a slump, which was frequent or wasn't healthy, also frequent.

Ken Harvey: When he was right, Ken Harvey could do some pretty awesome things with a bat. Unfortunately he was only right for about two minutes at a time.

Jim Eisenreich. John Castino. Curt Wardle. Ken Landreaux. Mark Fidrych. Brad Komminsk. SO many names from childhood.

Brandon Wood.

What about you guys?