This is a false question, since Danks is signed for two more expensive seasons and Hector Noesi could be dropped at a moment's notice. Yet they've had similar seasons and promise future utility going forward, which is to say they don't offer much.
They can't get many strikeouts, they don't counter it with particularly great control, they can't keep the ball low, they give up booming, gorgeous home runs, they somehow manage to sop up innings better than you would think. If you keep one of these guys at the back of the rotation, you won't be mad. If you keep two, you won't be too good.
Danks seems like the obvious guy to jettison if possible, on account of giving up 43 damn runs in his last nine starts. Hitters have hit (ugh) .340/.391/.573 against Danks during that time, and he's had 10 home runs launched off him in just 49 innings. He's struck out 12.5% of hitters, which is not enough. Not everyone needs to be Chris Sale, but striking out half as many batters as Sale is a little too low...and Danks is lower than that.
He wasn't like, particularly good before the slide, though. For all the plaudits he got for dragging in a sub-4.00 ERA into the All-Star Break, Danks was only striking out 15.9% of hitters, putting up a strikeout-to-walk ratio under 2.00, and was still coughing up dingers at over one per nine innings. He hasn't lost velocity, so while he can certainly be found making mistakes up in the zone all the time these days with blown changeups and fastballs that don't get inside, he never had a margin of error to begin with. Pre-All Star Break Danks deserved to be hammered and didn't, post-break Danks deserved it even more and got it enough to account for both halves.
Noesi has better raw materials, but continued talk about his success is confusing, since it's a stretch to say he's been average. It's kind of a mystery what off-speed stuff Noesi is going to have on a given day, and you have to wonder if Danks watches what Noesi does with an innate ability to throw 93-94 mph with natural movement and shakes his head in disgust.
Don Cooper might be instilling confidence in Noesi and getting the very best work out of him, but he's a disaster for this ballpark. He works up in the zone but doesn't miss bats consistently when he does like Quintana and most often has to rely on a changeup for his outpitch which tends to get very airborne when he misses with it. If it weren't for Danks' work, we'd be discussing Noesi's garish 22 home runs in 141 innings.
He has a 4.32 ERA as a starter, which is not particularly inspiring for purging or saving purposes. He's more consistently mediocre, which might explain the praise he's received. Noesi has started out hot plenty of times, but rarely finishes with a gem, but he rarely gets completely obliterated either, prompting the sense that "he keeps the team in the game," or keeps them just close enough for a below-average bullpen to look more blame-worthy. Danks has allowed six or more earned runs in six of his 28 starts. Noesi has just two in 23. An arbitrary cutoff for sure, but we're talking about perceptions here; arbitrary is the name of the game.
Their inability to miss bats gives them both the mixed blessing of breezing through low pitch-count innings. As a result, both log over six frames per start, proving that it's better to have a marginal talent than a erratic wunderkind at the back of the rotation. We all love Hector, but his common act of striking out six, throwing 110 pitches, then leaving after 5.1 innings would have been a disaster with this pen.
The Sox don't need another left-hander and they don't need things to spend money on, and would be better served to move Danks if they can, and replace him with a starter who can promise average and shoot for more. But given the unlikelihood, Noesi is probably not some great dynamo to regret casting aside. Most are simply shocked that the Sox have gotten this out of him. Because of his once-dastardly record, it's hard to project much success for him as a reliever. The Sox would understandably long to keep him around as depth, but doing that would probably produce a Dylan Axelrod-like result, where he is so bad at his unintended role that it drives off ideas of using him in his intended position.
In any case, the White Sox should keep one of them. Just one. Please.
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