The bullpen, led by Craig Kimbrel, Jonny Venters and Eric O’Flaherty, was a major strength for the Braves over the last few seasons. The only one of that Big Three left standing is Craig Kimbrel. Jonny Venters and Eric O’Flaherty are both injured. With O’Flaherty’s contract set to expire at season’s end and the possibility that Venters could be non-tendered, it’s very possible they won’t pitch for the Braves again. But how big a deal are the injuries to Venters and O’Flaherty?
Well the Braves have a slew of solid arms, both in the majors right now and in the minors. Kimbrel still seems healthy (knock on wood), Cory Gearrin has pitched well this season, as have Anthony Varvaro and Luis Avilan. Jordan Walden has looked dominant and hopefully his injury is not too serious. Julio Teheran or some other starting pitcher, if healthy, will go to the bullpen when Brandon Beachy is back healthy. Prospects J.R. Graham and Alex Wood and maybe even Sean Gilmartin could make a significant impact in the big league bullpen at some point this season. The Braves have some depth when it comes to arms.
However the biggest reason not to be all that concerned is that it’s very difficult for relievers to make a huge impact in the first place. If we look at the 2012 Fangraphs Wins Above Replacement leaderboard, only Craig Kimbrel and Aroldis Chapman were worth more than 3 wins above a replacement-level reliever. Remember a replacement level player is a readily available player that could be had for minimal resources. So basically it’s something like a Triple-A veteran. Only six relievers were worth more than 2 wins above a replacement-level reliever. Since the start of the 2005 season, no reliever has been worth more than 3.5 WAR in a single season. Since 1950 only four relievers have been worth as many as 5 WAR. Twenty position players were worth 5 WAR or more in 2012 alone.
Even the most valuable relievers have only thrown between about 55 and 85 innings in recent years. It’s just hard for a player to make a huge impact when he’s throwing that amount of innings. Even in an age when starters don’t go all that deep into games, the typical one still throws a good three or four times as many innings as a typical reliever.
So far this season O’Flaherty was worth a little under half a win above replacement level, according to Baseball Reference and hadn’t accrued even a fraction of a win above replacement, according to Fangraphs. Remember even the best relievers are typically worth somewhere between 2-3 WAR, so at worst the loss of O’Flaherty may cost the Braves 2-3 wins. However, with the Braves’ depth of arms it could be even fewer.