How can the Tigers replace Doug Fister?

When the Tigers sent Doug Fister to the Washington Nationals in exchange for three young players, the universal reaction from Tiger fans and the national baseball media was "they got what? For one of the best pitchers in the league?"

By most accounts, Fister was one of the best starting pitchers in the American League, in fact in the game of baseball, over the past three seasons. Over the past three seasons, Fister’s rank in the American league is
- Sixth in WAR
- Tenth in ERA
- Fifth in FIP
- First in HR/ 9 IP
- Third in BB/9 IP
- Sixth in Ground ball percentage
- Eleventh in innings pitched

Suffice it to say that Fister has a solid case for being one of the top ten pitchers in the league over the past three seasons. He was traded for a utility infielder, a LOOGY, and a left handed pitching prospect. Dissatisfaction with the trade from Tiger fans, in my view, is entirely justified.

But that horse has escaped and is gone forever. Dave Dombrowski had in mind a specific package of players that he wanted. Doug Fister ranked 35th in the league in strikeout percentage. He wasn’t the prototype flame throwing strike out pitcher that Dombrowski loves, so it was probably just a matter of time before he was traded, and Dombrowski got his package. Ask Jair Jurrjens, Burke Badenhop, or Casey Fien about that. More importantly, he unloaded $ 15 to 18 million in salary over the next two seasons for players who will make no more than the minimum over that span.

The plan, as has been announced, is to move Drew Smyly from the bullpen to the rotation, with Rick Porcello being expected to play a larger role, and probably expected to be part of the playoff rotation going forward. To say that Smyly will have to fill the void left by Fister's departure is not exactly accurate. Rather, the Tigers need Porcello to step forward and replace Fister's lost productivity, and Smyly needs to step in for Porcello. That scenario is much more likely to happen.

One concern with the former plan is that Smyly has never pitched over 100 innings in a season since making his major league debut. He worked 76 innings in 2013 out of the bullpen, and 99 innings mostly in the rotation in 2012. Add to that 17 innings in Toledo prior to his call up that season, and a total of 126 innings starting at two levels in 2011, and that’s the most he has thrown in one season. So, even if Smyly out pitches Porcello in 2014, whether he can be stretched into October duty is highly questionable.

The ideal plan then, would be to have Porcello step up his game to replace Fister, giving Smyly some periodic rest along the way. Is that possible? Well let’s take inventory. Following is a comparison of Fister, Porcello, and Smyly from the 2013 season.

What we see here is that Porcello is already ahead of Fister in GB% and K%. He’s also a bit better in WHIP, batting avg allowed, and K/BB rate. Rick is within striking distance in BB%, and in fact better than the three other starting pitchers on the Tigers last season in the walk rate. There is not a large gap between the two in won- loss record, but Fister has the better home run rate, and FIP.

Filling the void begins with making up the lost innings. Porcello threw over 30 fewer innings than Fister last season, only partly because he made three fewer starts. He'll need to pitch a bit deeper into games more frequently. Asking Smyly to throw 200 innings would be entirely unreasonable, but he could approach Porcello's work load from 2013 if he stays healthy.

The one area where Porcello falls way behind Fister is in ERA. He gives up more earned runs by a good margin. The primary culprit here is Porcello’s performance against left handed batters. Here are Porcello’s splits:

Vs LHH .299 .359 .449 .353 386 BF 60 K 31BB 11 HR

Vs RHH .234 .264 .337 .265 350 BF 82K 11BB 7 HR

In fact, Porcello had to face 16 more left handers to get through seven fewer innings (21 outs) than he did against right handers. Across the board, lefties have hit Porcello much harder than right handers. If he could only get left handed hitters out with more efficiency, Porcello could be able to take Fister’s place among the top ten pitchers in the American League.

Smyly, then, would need to pitch about 50 more innings than he has done in a season, and his numbers are already quite solid, although split between the rotation and the bullpen. Over the past two seasons, Smyly has a better home run rate, strikeout rate, batting average allowed, WHIP, and a significantly better ERA than Porcello. Smyly’s 76 innings in relief and his 1.9 WAR were both sixth in the league among relievers.

In fact the pitcher in the Tiger rotation with numbers most comparable to Smyly over the past two seasons is Justin Verlander. The two have nearly identical strikeout and walk ratios, the same batting average allowed, near identical WHIP ratios, and BABIP numbers, while Verlander has the edge in home run rate and is a quarter of a run better in ERA. Of course, that is not to say that Smyly is in Verlander's class. The big difference being that Verlander is a work horse, logging well over 200 innings per season.

There is no way to predict how pitchers will perform from one season to the next. That we can even talk about Rick Porcello and Drew Smyly in the same conversation with Justin Verlander and Doug Fister speaks well of the potential devastation that Tiger pitchers could heap on opposing lineups.

Verlander himself is, remarkably, a candidate for a bounce back season. Having spoiled us with two Cy Young level performances in 2011 and 2012, he fell back to being a mere mortal, but still easily a top ten pitcher in the league in 2013. The Tigers also had the greatest number of starts in the major leagues out of their top five starting pitchers last season. Should the injury bug bite them, their depth is questionable.

Replacing the loss of Doug Fister will not be easy. But if Rick Porcello can throw a few more innings and improve his game against left handed hitters, and Drew Smyly can do what he has been doing on a regular basis carrying the full load of a spot in the rotation, the Tiger rotation will be in great shape.