One of the biggest bullpen names in MLB celebrates his 35th birthday today. St Louis Cardinals lefty Andrew Miller has the 10th most bWAR of players born on 21st May in MLB history, behind Josh Hamilton, Matt Wieters and others.
Miller produced an historically great postseason for the Cleveland Indians in 2016. He was spectacular in 2017, but injuries followed and his numbers suffered in 2018. A free agent contract came soon after, at a smaller number than many had expected a year or so earlier. His first season with the Cardinals was comparable with his final year in Cleveland – results wise, at least.
The contract is far from crippling, and St Louis have a team option for 2021, but an effective Miller goes a long way to cementing the Cards’ place as National League Central favourites.
Relievers are notoriously volatile. Small changes can have significant results. A bounceback, even in his mid-thirties, isn’t impossible, but the advanced numbers give reason for caution when we project Miller in 2020 (assuming baseball takes place).
His expected ERA was up at 4.17 in 2019, markedly higher than 2018 (3.28). His strikeout rate has plummeted to 29% from 44.7% in 2016 and just below 40% the following year. He’s walking 10% of the hitters he faces.
Miller is missing fewer bats and giving up a load more barrels. That number was down at 3.3% in 2017, went up to 4.5% in 2018 and an ugly 8.8% last year. With his launch angle given up increasing too, hitters are setting themselves to do damage.
Age and injuries see pitchers lose their fastball. Miller’s four seamer was up at 95mph in 2017. It was just 92.4mph last season, giving up an xWOBA of .412 on the pitch, over 100 points higher than the same statistic in 2017. The fastball is dropping more as a result – it’s become a very hittable pitch.
Miller has always ridden his slider heavily. He’s lost a shade of velocity on it, but it breaks well above average. The slider gave up an xWOBA of .254 in 2019 along with a 36.3% whiff rate. Those numbers are worse than his peak in 2016 and ’17, yet it shows there’s still something to work with in Miller’s arsenal.
He fared much better against lefties in 2019 (.667 OPS vs .804 against righties). The backfoot slider remains a weapon, but the high fastball becoming less effective is particularly concerning against right handers.
The extra rest caused by coronavirus could help Miller. Perhaps it’s what he’s needed to fully recover from niggling injuries and find that old velocity and control on his fastball. If it remains a wild and 92mph pitch, however, his success in 2020 could come down to usage.
Lefty specialists have faded out of the game, and the three-batter minimum effectively nullifies them. The Cardinals will need to be selective with when they use Miller, though, and focusing him on lefties is the best way to do that.
He’s not going to be the pitcher he was in 2016 and 2017, but he could yet be a useful member of this Cardinals bullpen and a weapon in the postseason.