Veteran lefty reliever Andrew Miller is aiming to improve upon his 2019 season -- his first since signing a two year, $25 million pact with the Cardinals that includes an option for 2021. Last year, Miller showed occasional flashes of his vintage self, but overall he disappointed with a 4.45 ERA along with 26 unintentional walks and five unearned runs in 54 2/3 innings.

Going into his age-35 campaign, Miller seems unlikely to recapture the peak skill level that made him one of the game's top relievers for almost half a decade, but the hope is that he'll be an asset. On that front, though, there's discouraging news. Miller since last season has struggled with an imprecise malady. It's one that doesn't cause him physical pain but rather affects his ability to pitch normally. In describing what's wrong, Miller leans on the nebulous. Via Anne Rogers of, here's what Miller said: 

"I know what it feels like when I'm right. And I guess this is probably vague again. But the sensation I have throwing a baseball right now just isn't consistent with what it is when I know I'm good. It's just been a challenge."

As Rogers notes, Miller has undergone a battery of tests and met with the team's medical staff to try to pinpoint what's going on, but thus far there's been no obvious answer. It could be something mechanical, which presumably would be an easy fix, but according to Rogers the Cardinals are also open to the possibility that it could be a nerve issue. The fact that Miller is experiencing no physical symptoms, however, complicates the process of diagnosing him. 

The Cardinals still have bullpen depth, but Miller had been in position to get key outs in 2020, especially with closer Jordan Hicks still recovering from Tommy John surgery. Whether Miller can still provide the Cardinals with high-leverage innings depends upon whether this somewhat mysterious issue can be resolved. There's still time for that this spring, but answers prove elusive at the moment.