Pirates pitching prospect Jameson Taillon is the latest young pitcher to have Tommy John surgery. The news was a significant blow to the Pirates organization, and has already impacted some Fantasy leagues. While Taillon had yet to make his major-league debut, he was expected to be up at some point this season. That week, he would very likely have been one of the most added players in non-keeper leagues. In dynasty and keeper leagues, he was already considered one of the best pitching prospects to own.
Have you ever heard of the phrase "there is no such thing as a pitching prospect?" It was coined by Baseball Prospectus founder Gary Huckabay before Baseball Prospectus was even a thing. It's often abbreviated TINSTAAPP, because you know how much us stat nerds love acronyms. The saying isn't something to take literally, obviously. Plenty of pitchers who are now successful came up as some of the best pitching prospects in the game. But it still does make a strong point.
Pitchers, especially young ones, are not dependable. Pitchers in the lower levels of the minors need to develop at an expected rate, continue to have good enough stuff to advance through the minors and need to stay healthy enough to remain relevant. In Taillon's case, he proved the first two things. He was basically as close as any pitcher could get to being a true pitching prospect before his elbow blew up. Of course, Tommy John surgery is far from a death sentence. Taillon won't pitch this season, but should return, and possible pitch in the big leagues next year.
The point for Fantasy owners here is that it's tough to depend on young pitchers. They'll let you down, and occasionally break your heart. That's not to say Fantasy owners can't take shots on pitching prospects. In many cases last season, Gerrit Cole and Michael Wacha singlehandedly won leagues for teams. And in keeper and dynasty leagues, you can't just trade all your young pitchers away because they carry more risk. Unfortunately, it's just another sign pitching has become a necessary evil.