Koji Uehara and the Red Sox bullpen weren’t just average during their World Series run this past October. They were a major reason why they even won the title. However, repeating the kind of run the Sox bullpen established during the 2013 campaign will be incredibly difficult to replicate, especially when considering the concept of regression to the mean.
Hot streaks in baseball are difficult to maintain for a long period of time. That’s exactly what happened to the Red Sox bullpen last season. They had the 21st best bullpen ERA in the regular season at 3.70. However, they got hot in October and had a bullpen ERA of 1.28 over 49.1 innings pitched thanks in part to Uehara’s dominant performance where he didn’t allow a single walk and only surrendered one run.
There is no reason to believe that the Red Sox will jump out of the gate with those kind of numbers in 2014 and this is a cause for concern. While Boston has enough starting pitching and hitting to get to the playoffs this season, having a dominant bullpen is important in the playoffs. Since 2008, teams that had the lowest bullpen ERAs in a minimum of 10 playoff games went on to win the World Series.
One of the most glaring stats about the Red Sox bullpen from last season is the number of inherited runners they allowed to score – 34 percent. This means that over a third of the runners that were inherited by a relief pitcher came into score. These runs are reflected in the previous pitcher’s ERA. With that in mind, saying that the Red Sox bullpen ERA was 3.70 last season is not completely accurate because a lot of those runners were charged to the starting pitcher.
Red Sox pitchers also threw 23,990 pitches last season — seventh highest in the Majors and second-highest among the 2013 playoff teams. This is more on the relievers than the starters. Most starters are going to throw between 90 to 100 pitches in any given game. The total number of pitchers thrown in the game, though, is dependent on the relievers. If relievers get quick outs, then that number would be far lower.
Looking at individual pitchers, perhaps the one guarantee we can get from the Sox bullpen is Uehara’s accuracy. He didn’t walk a single batter throughout the entire playoffs and he had an otherworldly strikeout-to-walk ratio during the regular season with 101 punch outs to nine base on balls. This is the modern era record. The reason why it’s expected for Uehara to not walk any batters is because he’s always been that kind of a pitcher. He has only walked 38 batters in his five-year MLB career.
That said, as he becomes 39 years old, it’s going to be difficult for Uehara to replicate his outstanding numbers from last season. He had a career-best 1.09 ERA last season and a dominant World Series campaign. Throughout the process, the 38-year old Osaka native won the ALCS MVP, putting his name in Hall of Fame company along with Dennis Eckersley and Mariano Rivera as pitchers to have won the honors. That said, at 39, it will be difficult to match those honors.
Junichi Tazawa is another pitcher that had an impressive postseason run for the Red Sox. However, he had a 3.16 ERA in the regular season and he has a history of long-term injuries that have sidelined him in the past. He missed all of 2010 and almost all of 2011 due to injuries. What’s to say that those injuries can’t return? After all, players with injury histories are more susceptible to get hurt than those without them.
Other relievers like Craig Breslow and Brandon Workman were highly inconsistent last season. Breslow pitched a third of an inning in the World Series and bombed in it despite having a 1.81 ERA in the regular season. Meanwhile, Workman didn’t allow a single run in the World Series, but had an ERA close to five in the regular season.
Finally, the Sox also made a couple of free agency additions adding Edward Mujica and Burke Badenhop. Mujica pitched against Boston in the World Series as a member of the St. Louis Cardinals. He had an impressive 46 to 5 strikeout to walk ratio last season and could be a solid value signing for the team.
That being said, the Red Sox got hot in October. They may have had the best bullpen that month, but it was nowhere near the best bullpen in the entire season as evidenced by their high ERA and inability to hold inherited runners on base. If this continues, the Red Sox may be looking at a giant obstacle to overcome if they want to repeat.