Danny Duffy has been the only starting pitcher to make it to the majors after the Royals had the best farm system ever. Even his major league experience has been interrupted because of a Tommy John surgery. The surgery is not the major issue keeping down his production. It is the number of walks he freely gives out.
Here is his walk values over his first three seasons:
To put the number into perspective, Kyle Davies only had a career 4.3 BB/9. Over the past 10 seasons, only three Royals pitchers (min 100 IP total) had higher walk totals and all were relievers (Andy Sisco, Tim Collins and Robinson Tejeda). Finally, Duffy's walk totals are similar to Guthrie's strikeout totals over the same time frame (2011: 5.6 K/9, 2012: 5.0 K/9, 2013:4.7 K/9).
With such high walk totals, I wanted to go back and see if there were any comparable starting pitchers with similar innings pitched, strikeout and walk numbers to see if there is a chance for Duffy to turn around his career.
I looked at pitcher under 25-years-old since 1990 who what between 100IP and 200 IP and a BB% within two percent points of Duffy
Note: For walk rates I removed intentional walks.
First, only one pitcher had a BB% above Duffy which is not a good sign. The walk rate needs to go down to the 11.4% level for some productive pitchers (Sanchez and Buchholz) to emerge. Additionally, quite a few relievers are on the list (Howell, Hernandez, Rzepczynski and Gagne), so maybe another failed starter can move to the Royals bullpen. Just looking over the list, it doesn't give me a good fuzzy feeling for Duffy's future success.
Now, limiting the list to pitchers with similar K% (+/- 2% points), I end up with:
Again, some good, a lot of crap
For Duffy to ever make it as a regular pitcher, he needs to get his walks under control or he will end up in the bullpen with the rest of the fail Royals starters.