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The San Francisco Firemen

When you think of the San Francisco Giants bullpen, you think of Brian Wilson. Since assuming the closer’s role four years ago, Wilson has been the face – and the beard – of relief pitching in the Bay Area. That recognition comes with merit since the right-hander has been one of the better relief pitchers in baseball and his save totals (160 since 2008) shows he is well-equipped with the closer’s mentality. While he has done a great job closing the door, the pitchers bridging the gap from starting pitcher to Wilson has been as good, if not better.

As a unit, Bruce Bochy’s bunch has been a top-3 bullpen this season. More specifically, he has deployed a lefty/righty combination of high-leverage relievers to lock down the innings prior to his closer. From the left side, Javier Lopez has been quite the pickup for the Giants since joining the club in late 2010. As an alumni of the FanGraphs’ school of higher leverage, Lopez has settled in as one of the more dependable lefties in relief.

Coming into Wednesday evening, Lopez had tossed 42 innings with a 2.57 ERA and a 3.16 FIP. His xFIP of 3.92 is much higher; however, he is an extreme groundball pitcher with GB rates above 60% in each of the last two seasons. Because of this, his home run rate is usually below the norm, meaning he is a perennial candidate to outperform his xFIP. Lopez has taken that theory to the max this year as the lefty has yet to allow a home run to any of the 174 batters he has faced.

The one flaw with Lopez comes in the form of splits. Not uncommon for his skill-set – a soft-tossing, left-handed reliever – right-handed batters have much more success against him their left-handed counterparts. Despite the difference in effectiveness (3.94 FIP vs. RHB, 2.45 FIP vs. LHB), Lopez has actually faced more RHB (92) than LHB (82). Considering some of the non-closing, right-handed pitchers available in the Giants’ bullpen, this is a rather unnecessary exercise.

One of those right-handers is Sergio Romo. Despite his small stature (listed at 5-foot-10 and 185 pounds) and his relative lack of “stuff” (average fastball velocity of 89.5 this season), Romo can rack up strikeouts with the best of them. Among qualified relievers, his 12.87 K/9 ranks sixth best in the major leagues. Where Romo sets himself apart from his fellow strikeout artists is command and control. Of the five names above him, only Vinnie Pestano of the Cleveland Indians has a BB/9 less than 3.00. Romo, on the other hand, has a BB/9 of 1.01. While striking out 52 batters this season, he has allowed just four walks and one of those was intentional.

Unlike his left-handed partner, Lopez, Romo has been deployed as a specialist by Bochy. Although he has shown the ability to get left-handed batters out (2.84 FIP/4.00 xFIP career), Romo has pitched with the platoon split to his advantage 72% of the time this season. That ties him for the highest rate among relievers with at least 30 innings pitched. Oddly enough, he is tied with teammate and fellow right-hander Ramon Ramirez, another sign that Lopez should not be facing as many right-handed batters.

Because he has been death to righties (0.44 FIP/0.84 xFIP) and his manager has put him in favorable situations most often, Romo has become a true relief ace. In fact, he leads the majors in both FIP (1.20) and xFIP (1.56) for relief pitchers. Since he is used so systematically, he has pitched just 35 innings despite 50 appearances; however, those 35 innings have been worth 1.6 WAR.

While Wilson will continue to rack up the saves – and therefore all the glory – it is the work of Lopez, Romo, and others – like Ramirez and Jeremy Affeldt – that afford him with the opportunity to shine in the ninth inning. Although they may never appear on the Rolaids Relief Man leaderboard (that would currently be…Brian Wilson), it is the unsung members of the San Francisco pen who are putting out the early inning fires before Wilson is able to cross his arms and signify another Giants’ victory.