Detroit Crash Course: Tigers’ Bullpen is Endangered

Joe Nathan

It seems to be the current theme in Detroit, “if only we had a bullpen.” That was the main concern for the team going into the 2014 Major League Baseball playoffs. This is what was written about the Tigers going into their playoff series against the Baltimore Orioles:

While the Tigers have the star power in the rotation and in their lineup, they are sorely lacking on defense and out of the bullpen, which also proved to be their Achilles’ heel in the 2013 playoffs as well.

Guess what? We are witnessing pretty much the same team going into the 2015 season. The Tigers will once again count on the same guys that pretty much imploded last year. Will this year be any different?


Joe Nathan has been awful in Detroit, but he acts like an elite pitcher. At least when it comes to answering the local fans. In an article written by our resident number one Detroit Tigers’ fan, Tomas Laverty, when Nathan was asked about his struggles, he basically blamed the fans:

“I think a lot of it is lack of knowledge,

“I think they got frustrated from the first couple months of how I pitched – rightfully so – but the thing is for me the last couple months recently, things have gone well. I’ve pitched well, and not just myself but other pitchers coming out of the pen, just to name one Phil Coke, who threw the ball outstanding.”

And then Nathan would go on to have a terrible season. So maybe the Tigers’ fans are not as dumb as Joe Nathan would believe.

Entering his age 40 season, Nathan is coming off one of his worst seasons of his career. Among relievers pitching a minimum of 40 innings, Nathan finished in the top 25 in terms of highest Walk Rate (BB%), the highest it’s been since 2003. He coupled a high BB% with a low Strikeout Rate (K%), resulting in an awful Strikeout:Walk ratio (K:BB), finishing among the lowest 25 among relievers. It’s almost miraculous that his 2014 Field Independent Pitching (FIP only takes into account a pitcher’s walks, strikeouts, and home runs) did not go over 4.00 . He basically produced like Javy Guerra or Aaron Loup. Unfortunately, Nathan is getting paid a lot more money than those two relievers combined.


Nathan has posted three consecutive seasons of Line Drive Rates (LD%) above 20 percent. Nathan posted a top 50, LD% of 22.5 percent in 2014. He induced more ground balls than fly balls, but not enough to be considered a true ground ball pitcher. A similar batted ball profile to Nathan’s can be seen in–you guessed it–Javy Guerra.




Joe Nathan

.324 22.5 41.6 35.8 8.1 8.1
Javy Guerra .288 21.4 40.5 38.2 8.0



Nathan has been attempting to compensate for a declining fastball (now below 92 mph) by throwing more sliders as he tries to become a more balanced pitcher. The difference in fastballs and sliders for Nathan is 6.8 percent. There were 31 relievers that threw sliders more than 32 percent of the time they were on the mound. Of those pitchers (besides Nathan), only five saw a difference below seven percent between their slider usage and second pitch frequency:

In terms of ERA/FIP, all of these pitchers had much better seasons than Nathan, including Neal Cotts. So it is possible to be successful while throwing heavy doses of sliders and not really having a true primary pitch. But the reason these pitchers have gone to a balanced approach is because their fastballs will not blow many hitters away. With the exception being Ottavino, all of these pitchers had average fastball speeds below 92 mph. Somehow, they found ways to adapt and be effective.


Nathan’s Swinging Strike Rate (SwStr%) and Contact Rate were the second worst of his career (2011 was his worst in both categories). In 2014, Nathan had a Contact Rate against of 78.7 percent, placing him among the top 60 highest in this category. SwStr% was among the top 50 lowest in the Majors. And based on his Swinging Percentages, hitters are getting more patient with Nathan. He’s not inducing many swings and hitters know he’s attempting to paint the corners. Basically, the analytics suggest that when batters go up to the plate, they might as well be playing tee-ball.


As mentioned, the Tigers have alternatives–the same alternatives from last season. And it’s only a matter of time before Nathan has to relinquish his role as a closer. Here are the top candidates to take over said role.

Joakim Soria: Was having a good 2014 season in Texas but then he got to Detroit and caught whatever illness was ailing the Tigers’ bullpen. But he posted a K% that had him finishing among the top 50 relievers and a microscopic BB%. He finished with a top 15 FIP. He finished with a top six pop up rate among all relievers last year. In the last three years, he’s averaged a pop up rate of 17.4 percent.

Soria’s fastball is actually slower than Nathan’s (average of 90.3 mph in 2014) and he threw it a career low 34 percent of the time. He’s been trying to utilize his cutter and breaking pitches more. His cutter might end up being his primary pitch as he grows older.

But just like Nathan, Soria is struggling to induce swings and has a similar Contact Rate to Nathan’s. Although his production would suggest that he should be the closer, he doesn’t really fit the profile of a dominant closer. Then again, as he gains more confidence to throw the cutter at a higher rate, perhaps his plate discipline numbers will improve to the way they were when he was the closer for the Kansas City Royals.

Joba Chamberlain: His first season as a Tiger resulted in him appearing in the most games since 2010. His FIP was middle of the pack, but he did cut back on the home runs, which was plaguing him in his last three seasons as a Yankee. However, Chamberlain’s BB% was among the top 60 highest among relievers last season and this would end up being his doom.

Chamberlain is a true, ground ball pitcher (53.2 percent GB%, finishing in the top 40), but finished with the 41st highest LD% in 2014. So even though he’s inducing more grounders and giving up less home runs, he still managed to have a high LD%. That is so Joba.

Chamberlain’s fastball averaged 93.4 mph, but that’s a decrease of more than one mile from 2013, so that’s a bit of a red flag. While he’s using his fastball less every season, he’s thrown more breaking pitches in the last three seasons, more noticeably, we saw a spike in his curve ball. Matter of fact, he was among 15 pitchers who threw the curve more than 20 percent of the time last year.

Just like his other two teammates, Chamberlain does not induce a lot of swings as hitters are more than willing to wait for that pitch in the strike zone, where they are making contact 86.2 percent of the time. He did have a modest SwStr% (10.7 percent) so it appears his mid 90s fastball and breaking pitches seem to be doing something right.

Al Alburquerque: We mentioned Alburquerque in our Astros’ preview of their bullpen issues. His primary pitch is a slider. As we mentioned in that piece, pitchers that primarily throw sliders are not counted on to make saves. Sergio Romo, who also throws a slider as his primary pitch, was the exception. And then he lost his job because he struggled to keep the ball in the park. Well, Alburquerque also struggles with the long ball. He would finish the 2014 season with a Home Run Per Fly Ball Rate (HR/FB%) of 13.2 percent, finishing among the top 20 highest relievers in this category. Romo would finish 21st.

Alburquerque finished with a really good K% of 26.7 percent (slightly ahead of Soria). He also had some issues with walks. Along with the home runs, Alburquerque posted a high FIP of 3.78 (finishing in the top 50 highest, behind teammates Nathan and Coke).

Nevertheless, because his slider is a potent pitch, he has one of the lowest contact rates among relievers and his SwgStr% of 13.9, though a career low in 2014, still had him finishing among the top 25 highest in baseball.


It would appear that Nathan will be the closer by default to kick off the season, but he’s on a very short leash. Soria should get a chance to be the next man up, probably by the end of April, at least for the simple fact that he has shown an ability to keep walks in check and forces a lot of pop ups. If he continues to be effective with his cutter, who knows? Maybe the Tigers have a homeless man’s version of Mariano Rivera (a really big if). Chamberlain appears to be wanting to rely more on breaking pitches to get by in the Majors. Meanwhile, Alburquerque has the plate discipline (high Swinging Strikes, low Contact Rate) to be a closer, but lacks the control and command to be effective.

All stats courtesy of

Depth charts courtesy of Roster Resource.

author avatar
Felipe Melecio
Felipe Melecio was the managing editor for the blog Pathological Hate. He believes that math is your friend and numbers can be fun, especially when it comes to baseball. Keep tabs on all his knee-jerk reactions on Twitter: !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);;js.src=p+'://';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');