The two most significant injuries in 2012 came at the expense of the starting rotation when Danny Duffy and Felipe Paulino needed Tommy John surgery. Paulino had 37.2 solid innings to follow up on good numbers with the Royals in 2011 and Duffy was the only highly-ranked starting pitching prospect to even reach the majors to that point.
Duffy made it to May 13 with surgery coming a month later. Paulino threw his last pitch in Kansas City on June 6 and had surgery on July 3.
Going into the 2013 season, both will still be rehabbing. The typical timeframe these days is about a year, though, of course, every arm and injury is different. John Lamb had Tommy John surgery on June 3, 2011 but his return didn’t come until the middle of last August (though the delay turned out to be more related to an ankle injury that popped up than any slow recovery of the arm). A typical schedule could put Duffy in line to return next June and Paulino just before the All-Star break, assuming no setbacks.
But then they also need to have some rehab starts. Figure on at least a month for each, so that pushes it back to July for Duffy and August for Paulino. That limits the amount of impact they may have on a 2013 Royals team (though could still turn into 10 starts for Duffy and six or so from Paulino).
There’s also the question of how effective they may be when they come back. While most pitchers can return to regular duty within a year, they’re not fully effective until a year and a half or so.
A study done by Jeff Zimmerman and Brian Cartwright for the 2013 Hardball Times Annual noted that pitchers generally see a jump in their ERA and HR/9 rates in the first year back from Tommy John surgery. Those combined 16 starts may not be very meaningful aside from getting both pitchers back into the routine of being a part of a big league rotation. By the second season back, performance returns to the normal projected levels. Zimmerman and Cartwright used Stephen Strasburg and Jordan Zimmerman as recent examples of this pattern. So in 2013, it’s a safe bet that in a shortened season, Paulino and Duffy will see worse numbers than they’d left with.
It makes it a bit more difficult to evaluate Duffy in that regard because his overall sample size in the big leagues isn’t very large as he hasn’t quite made the normal full season equivalent number of starts and is still a bit of a question mark. It won’t be entirely certain if he fits a pattern if 2013 is rough and 2014 is much better or if it’s simply his own development. In his six starts last year, his hits and homers per nine innings had both gone down while his strikeout rate had risen. Those are good signs, despite an increase in walks per nine innings. His xFIP of 4.77 would have been an improvement over his 5.64 ERA in 2011 (but not his 4.53 xFIP that year).
Duffy looks like an average major league starter with upside to be much better, so those are the signs to look for in 2013 with an eye toward a solid leap in 2014. Based on the historical data, Duffy’s probably due to be stuck in place a bit in his couple months of time.
Paulino’s not an easy guy to nail down either. He struggled so much in the National League before the Royals took a chance on him and were rewarded. His body of work leans much more towards the bad than the good, though his recent results are favorable, especially his start to 2012. But we still don’t really know. He’s always looked like he should be a better pitcher based on his fielding independent numbers and to watch him, he does have the kind of stuff that would seem to make him a good pitcher.
His 2013 could be right around average in his limited time. After parts of two seasons where he had 177 innings and a 3.86 ERA (combining his Colorado and Kansas City stats), so if he follows the pattern, that would put him in the 4.50 ERA range. Both pitchers could contribute once they return but it’s not safe to assume that their return will push the Royals towards a late-season playoff run.
An aspect where neither pitcher follows the pattern is their velocity. There’s usually a drop in velocity on a fastball from year to year (just based on age and wear) but a larger drop can signal a problem. Neither Paulino nor Duffy had sharp drop. Duffy even gained two MPH on his fastball from 2011 to 2012 (though it could have dropped as the 2012 season wore on if he’d seen 30 starts, nonetheless he was averaging 95 MPH when he was shut down). Paulino’s fastball velocity started increasing from 2007 to 2010 but not in a huge chunks. He went from 95.3 to 95.4 to 95.5. In 2011 and 2012, he averaged 95.1 MPH on the fastball. That’s not a sharp drop at all.
What might be most important to watch is their velocity in 2013. There’s not as strong of a pattern to pitchers coming back from surgery and having it affect their velocity. Some lose speed, some gain. Some stay the same. They’re both hard throwers and I think their secondary pitches would be more effective if they were to remain that way. If that’s the case, 2014 could be a fun year to watch both.