The modern bullpen is constructed from the back forward, and there is no greater practitioner of pitching a baseball in the ninth inning than Craig Kimbrel, a small-statured (5-foot-11), baby-faced (25 years old) righthander who mixes a 98-mile-per-hour fastball and a sharp-turning slider to such devastating effect that he inspires respect that belies his roster listing.
Kimbrel has now topped 40 saves in each of his three full seasons with preposterous efficiency -- consecutive ERAs of 2.10, 1.01 and 1.03 as well as a combined strikeout rate of 15 per nine innings -- to give an overwhelming sense of security any time Atlanta holds a lead after eight innings.
While Kimbrel has become as reliable and dominant as any closer in baseball, what's been most remarkable about the 2013 Braves has been the effectiveness of the changing parts in front of him even after losing two of the game's best setup men, Jonny Venters and Eric O'Flaherty, for the season.
"Those two were top-flight lefthanders in the entire game, and when you lose two guys like that early in the year, you're not sure that you have enough pieces to be able to overcome that," Atlanta general manager Frank Wren said. "It's a credit to our guys that they've stepped up and picked right up where they've left off."
The Braves' 2.42 bullpen ERA is not only tops in the majors this year, but it is also the best of a set of relievers since the AL pennant-winning, Dennis Eckersley-led A's in 1990. Instead of Venters and O'Flaherty, it's been Luis Avilan and Jordan Walden, with David Carpenter, Anthony Varvaro, Alex Wood, Luis Ayala and Scott Downs filling out the bullpen to great effect this season. Braves relievers lead baseball in opponent batting average (.217) as well as fewest homers (20) and hits (291) allowed while ranking fifth in the rate of stranding inherited runners (74.1 percent).
Atlanta is 57-2 when leading after six innings this season after going 77-4 in such situations last year for a combined winning percentage of .957 -- well above the league average of .871.
Since the beginning of the 2009 season, in fact, the Braves' bullpen has been about a quarter-run better than the field -- its ERA in that time frame is 3.02 while the Padres rank second with a 3.24.
"I think we recognize that there's some volatility in every bullpen, and you can't assume performance year to year," Wren said. "One of the things that has been successful for us is that we're continually looking to add. That's where our scouts are very aggressive in recommending because they know we're looking to create depth all the time."
Relief pitching has a high rate of attrition and is a profession fraught with a high injury rate and erratic deviations in performance. When Medlen was a rookie reliever in 2009, he said he learned the trade from Rafael Soriano, Mike Gonzalez and Jeff Bennett. In the four seasons hence, Gonzalez has pitched for four different teams, Soriano for three and Bennett hasn't pitched in the majors at all.
"I think it's just a confidence that the organization instills in these guys that they're not shy throwing them in the fire and practically learning on the job," said Medlen, who was primarily a reliever in the majors before joining the rotation for the final two months last season. "I mean, where did Carp come from?"
Indeed, where did the man with a 1.98 ERA in 50 innings come from? Well, Carpenter has been traded three times -- in a waiver trade for a veteran (Pedro Feliz in 2010), as part of a pre-deadline package for two veterans (Francisco Cordero and Ben Francisco in July 2012) and in a trade for a manager (along with Mike Aviles to Boston for John Farrell last October) -- and ultimately reached the Braves through a waiver claim on Nov. 30, 2012, which also happened to be the same day the Braves acquired another hard-throwing righthanded reliever, Walden, in a trade with the Angels for Tommy Hanson. (Wren said the Braves had sought Walden since he was a minor leaguer.)
"You see those four guys coming," Carpenter said, referring to Walden, Kimbrel and the then-healthy Venters and O'Flaherty, "I was thinking, 'Daggone, it's going to be pretty full in the back end of the bullpen.' I was just hoping for an opportunity, whether it was long relief or some mop-up innings just to come up and contribute the best I could."
Carpenter, Varvaro, O'Flaherty and fellow reliever Cristian Martinez were all waiver claims, meaning Atlanta's scouting apparatus has had a keen eye for finding value where other teams didn't. Of the key contributors in front of Kimbrel this season, only Avilan and Varvaro were with the Braves in 2012, and even then the pair combined for fewer than 50 innings. Now Avilan has a 1.33 ERA and a team-leading 21 holds.
Combining turnover with consistency indicates what a strong culture and infrastructure the Braves have put in place. Medlen said McDowell -- a career reliever himself who logged more than 1,000 career innings of relief and saved 159 games with the Mets, Phillies, Dodgers, Rangers and Orioles -- has been "a huge part" of the success while Carpenter praised McDowell's attention to detail. McDowell said the club utilizes all the advanced statistical information and video tools to prepare for matchups.
McDowell praised manager Fredi Gonzalez's expert deployment of the relievers in the sixth and seventh innings ahead of the close-game mainstays of the later innings. Additionally, bullpen coach Eddie Perez was previously Greg Maddux's personal catcher. Among the current catchers, Brian McCann is in his ninth season with the organization, free agent signee Gerald Laird is noted for his defense and rookie Evan Gattis has prepared alongside those veterans.
And there are no obvious common styles shared by all the relievers. Kimbrel, Walden, Carpenter and Wood all have K/9 rates of 9.5 or higher; Ayala and Avilan, on the other hand, are groundball specialists with K/9's below 5.5 but groundball rates of 70 percent.
Although the 2011 Braves bullpen appeared to wear down during the club's awful collapse -- the big three each had 78 or more appearances -- that owed largely to an extraordinary number of close and extra-inning games in the season's first half rather than any penchant for quick hooks of starters. In fact, the '13 Braves bullpen is the third-least-used in the majors based on its 2.85 innings per game rate, which trails only Detroit and Cincinnati. Increasingly, Gonzalez has shown a deft touch in seizing the moment in the middle innings with a call to the bullpen while also balancing workloads.
One of the biggest reasons for that, McDowell said, was Greg Walker, the club's second-year hitting coach who has overseen the No. 2 scoring offense in the NL. "We add on runs after the fifth inning," McDowell said. "In his words, fight the fight every at bat."
Most of the credit, of course, goes to the relievers themselves, who have maintained their high level of performance despite a regular influx of new faces.
"Every year there's been that one guy who's been the veteran who shows you the ropes, keeps you on your toes and doesn't let guys slip, and for some reason it's Craig," Medlen said with joking bewilderment of his younger teammate. "Craig is the veteran of the 'pen. The stuff he throws up there, it's no surprise the numbers that he has."
The bullpen starts with Kimbrel, but its success is the result of the whole.