Why Cardinals sacrificed reliever to take chance on 2020 Braves first-round pick

Prior to their series finale in Detroit, the St. Louis Cardinals shuffled their bullpen depth chart around, promoting southpaw Jared Shuster to the big-league club. In turn, the team optioned Chris Roycroft, though they also had to free up a 40-man roster spot, hence why they designated Nick Raquet for assignment.

That's a lot of moving parts to fill one roster spot, but the move makes ample sense when you look a bit deeper. First, the Cardinals could not call up an arm already on their 40-man roster prior to Friday due to option rules, which means arms have to spend at least 15 days in the minor leagues before being able to be recalled. 15 days from Opening Day is on April 9th.

Also, the only left-handers in the bullpen prior to Shuster's arrival were JoJo Romero and Justin Bruihl, the latter of whom threw on two consecutive days prior to the final game against the Tigers.

With Bruihl (and most of the rest of the relief corps) struggling with command issues in the early going, the team has opted to take a chance on a former first-round pick in Shuster.

Jared Shuster can extend his stay with Cardinals by flashing better command

Of the seven other members of the bullpen, only two are walking fewer than 6.75 batters per nine innings: Romero and closer Riley O'Brien.

All of that is coming from a small sample (no one has thrown even six innings yet), but that it's such a widespread problem speaks to what the Cardinals are trying to solve by promoting Shuster.

Though he's never been particularly effective at the MLB level, Shuster did significantly improve his command last year with the Chicago White Sox. His walk rate was down to 6.1% across 12 appearances, leading to some of the best metrics of his career: a 31.3% chase rate, 4.8% barrel rate, and a 2.94 FIP that suggested he deserved far better than his actual results (8.04 ERA).

He'd only made one Triple-A appearance this year prior to the promotion, and he got hit hard while allowing four earned runs in three innings. Still, he walked no batters in the outing, and Oli Marmol's need for a dependable third lefty in the bullpen forced the issue. Shuster will need to pitch much better to stick around in St. Louis for the long haul, but the team invested little into him; a late breakout from a former top prospect would be an unexpected win during a rebuilding year.

Meanwhile, Roycroft was struggling badly in the majors before the move. He was issuing free passes to everyone in sight (20.0% walk rate) and generally looked lost on the mound. He'll get a chance to right the ship in Triple-A, but don't expect to see him back in the big leagues until he can figure out how to locate the strike zone again.