Editor's note: Over the next two weeks, we will examine 10 A's players who might or might not return to Oakland next season. For each player, we will provide reasons why the A's should bring him back and reasons why they should not, followed by a final determination.
Jake Diekman, LHP
Contract: $5.75 million mutual option for 2020 ($500,000 buyout)
Reasons to bring him back
Diekman's stuff is undeniable. The 32-year-old left-hander boasts a 96-mph fastball along with a wicked slider, making him a tricky at-bat for right-handed and left-handed hitters alike.
Despite a 1-7 record and 4.65 ERA this season, Diekman notched 84 strikeouts in just 62 innings. For his career, he has averaged 11.2 punchouts per nine innings.
Another reason to keep Diekman is Oakland's lack of left-handed relievers. Jesús Luzardo and A.J. Puk both figure to move to the starting rotation next year and Ryan Buchter's return is far from certain. As a result, Diekman could be the only southpaw in the A's bullpen.
Reasons to let him go
While Diekman's strikeout numbers were highly impressive, his lack of command became a major issue down the stretch. He walked 39 batters this season, including 16 in 20 1/3 innings with the A's.
That contributed significantly to Diekman's disappointing 1.42 WHIP and 4.65 ERA. For $5.75 million, you'd have to think the A's would want someone more consistent and reliable in the late innings.
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Oakland is unlikely to bring Diekman back next season for a couple of reasons. Far too often, he just doesn't know where his pitches are going. Throughout his career, Diekman has averaged five walks per nine innings. That's a serious problem for a setup man.
The other factor is Diekman's $5.75 million price tag. That is a high figure for any non-closer, but particularly worrisome for a setup man who has proven to be inconsistent.
The A's would probably be wise to spend that money elsewhere.