If any fans feel annoyed this offseason about their team not spending to strengthen the bullpen, they might want to look at what is happening this year across Major League Baseball.

A long rehab for Philadelphia Phillies reliever David Robertson got much longer on Saturday as the 34-year-old underwent Tommy John surgery. The dreaded surgery will cost Robertson, who went on the injured list back in May, the rest of 2019 and likely the entire 2020 season as well.

Robertson signed a two-year, $23 million contract with Philadelphia in free agency last offseason, and now it looks like he’s going to spend all but a month of his Phillies tenure on the injured list. In that month, he had a 5.40 ERA. The Phillies didn’t exactly get great value there.

What’s so sad about Robertson’s turmoil is that up to 2019, he was as steady a reliever as you could find in baseball. In the decade preceding this season, Robertson posted an ERA above 3.50 just once in 10 seasons. He posted fewer than 60 innings just once in 10 seasons. He posted a K/9 above 10 in all 10 seasons, moving between set-up duties and closing.

Robertson was a rock for his entire career, and then he wasn’t. His deal is now a bust for the Phillies, and he isn’t alone.

Nearly every big reliever contract was a disaster this year (except for one team)

Incredibly enough Robertson isn’t the exception in how major reliever contracts from last offseason have gone. He’s the prime example.

Here is a list of every reliever who got more than $5 million in free agency last offseason according to Spotrac, their ERA this season and how many times they’ve hit the IL:

• Craig Kimbrel (Cubs, $43 million): 5.68 ERA, one trip to IL

• Zack Britton (Yankees, $39 million): 2.13 ERA

• Jeurys Familia (Mets, $30 million): 6.30 ERA, two trips to IL

• Adam Ottavino (Yankees, $27 million): 1.70 ERA

• Andrew Miller (Cardinals, $25 million): 3.79 ERA

• Joe Kelly (Dodgers, $25 million): 4.69 ERA

• David Robertson (Phillies, $23 million): 5.40 ERA, one trip to IL

• Kelvin Herrera (White Sox, $18 million): 6.88 ERA, one trip to IL

• Joakim Soria (Athletics, $15 million): 4.79 ERA

• Justin Wilson (Mets, $10 million): 2.66 ERA, two trips to IL

• Cody Allen (Angels, $8.5 million): 6.26 ERA, one trip to IL, DFA’d

• Jesse Chavez (Rangers, $8 million): 4.85 ERA, one trip to IL

• Trevor Rosenthal (Nationals, $7 million): 13.50 ERA, one trip to IL, DFA’d

Yikes.

What’s behind big-money relievers’ big ERAs?

That is more than $250 million spent on 14 relievers and basically two truly successful seasons to show for it. And they (Britton and Ottavino) are both on the Yankees, because of course.

The trade market wasn’t a whole lot better, as the New York Mets’ megadeal with the Seattle Mariners for closer Edwin Diaz and Robinson Cano is looking like a disaster with Diaz currently holding a 5.44 ERA. At least Alex Colome is doing pretty alright (2.30 ERA) with the Chicago White Sox after getting dealt by the Seattle Mariners.

Last year might have been even worse for relievers, as exemplified by the Rockies’ awful, awful, awful bullpen (each of those “awful’s” symbolizes a player who got more than $25 million and didn’t post better than a 4.00 ERA).

In fairness to this year’s crop of free-agent relievers, they are dealing with the highest run-scoring environment since the steroid era thanks to the clearly juiced ball. Of course, their numbers are still bad compared to the rest of the league, and any troubles due to bad luck just show the volatility you deal with when you’re a reliever or a team heavily invest in relievers.

None of this is to say these relievers don’t deserve the kind of money they got last offseason. They didn’t make teams give them those contracts. It simply means that just because you throw a bunch of money at a shutdown reliever, it doesn’t mean you’ll be getting a shutdown reliever in return (unless you’re the Yankees, apparently).

Relievers have always been among the most volatile investments in sports, and they’re getting only more turbulent as velocities, home run rates and arm injuries keep increasing.

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