5 Cardinals relievers who are showing their prowess in Spring Training

Riley O'Brien

The St. Louis Cardinals acquired Riley O'Brien in a trade with the Seattle Mariners in a minor trade back in November. O'Brien, 29, has seen some MLB action, but he has toiled in the minors for the better part of 7 seasons. He was drafted by the Tampa Bay Rays, but he has also played for the Cincinnati Reds and Mariners.

When the Cardinals acquired O'Brien, the needle wasn't moved on their 2024 season outlook. He was going to compete for a roster spot in the spring, but fans didn't expect much out of the righty. His 28.6% walk rate compared to his 21.4% K rate in very limited time in the majors will stifle even the most optimistic pundit's analysis.

His minor league numbers were much more promising, however. He sported a 27.1% K rate compared to just an 11.8% walk rate in the minors. O'Brien's 3-pitch mix of a sinker, a cutter/slider, and a curveball is nasty. He has some of the greatest horizontal break in the organization on his pitches.

O'Brien's sinker averages 95 MPH and has more than 15 inches of horizontal break to it; it generates a lot of soft contact on the ground as well (71.4% groundball percentage in the majors). His curveball (potentially now a sweeper) is his best pitch, and its high velocity paired with insane horizontal break help the pitch generate whiffs at a best-in-league rate.

This spring, O'Brien has pitched in 5.4 innings. He has struck out 3 batters, walked 1, given up 4 hits, and has yet to give up a run. O'Brien's appearance on the major league roster hinges on a strong spring. He has proven his worth in just under a month of performances.

Drew Rom

Drew Rom was another 2023 acquisition. Via the trade deadline fire sale, John Mozeliak was able to bring in Rom, a left-handed pitcher who focuses on command. While his fastball (91 MPH average velocity) won't blow anyone away, he is able to locate his pitches on the outside of the strike zone.

The Cardinals received Drew Rom, 24, in a package in exchange for Jack Flaherty from the Baltimore Orioles. Rom stands 6'2", and he uses a three-quarters arm slot for the majority of his pitches. Though he was never a top prospect, he still made Baltimore's organizational top 30 in a deep farm system. Rom was recently ranked the Cardinals' 29th-best prospect in MLB.com's rankings.

His minor-league stats are decent. Rom sported a 3.71 ERA, 1.314 WHIP, and 10.6 K/9 across 101 appearances (89 starts) and 450.2 innings. The Cardinals were desperate for pitchers with strikeout potential last year, so their targeting a guy who strikes out batters at a 27.5% clip made total sense. St. Louis immediately sent him to AAA Memphis but called him up for 8 starts at the end of the season.

Rom's sweeper is probably his best pitch of the 4 that he throws, but he did not have a single plus pitch last year according to Baseball Savant. Rom generates a decent horizontal break with his sinker (15.6 inches).

Drew Rom's introduction to St. Louis last year was uninspiring; he appeared in 8 games--all starts-- and pitched 33.2 innings. His 8.02 ERA was exorbitant, and his 18.8% K rate paired with an 11.2% walk rate gave many fans worry, justifiably so.

Rom appears to have put his MLB debut behind him this spring. He has pitched in only 5 innings, but he already has 5 strikeouts, only 1 walk, and he has allowed only 1 hit and no runs. Rom pitched 3 shutout innings on Sunday's game despite several pitchers around him allowing runners to score. If he can continue to pitch this well, he may fill one of the final spots in the bullpen in 2024.

In order to make the rotation out of the gate, Rom will have to jump Zack Thompson, Matthew Liberatore, and likely Gordon Graceffo in the depth chart. Rom's ability to pitch multiple innings is an attractive attribute out of the bullpen, however.

Andrew Kittredge

Andrew Kittredge is another new face on the roster this year (well done, Mo!). In a somewhat controversial trade, the Cardinals shipped young outfielder Richie Palacios to the Tampa Bay Rays for a recently recovered Andrew Kittredge. Kittredge missed all of 2022 and most of 2023 due to Tommy John Surgery. 2023 was his first season back from the injury.

Kittredge throws from the right side and stands in just over 6 feet tall. The righty will turn 34 in just a few days. Kittredge's best season was 2021, the same year he made the All-Star Game. He has a career 3.65 ERA, 1.230 WHIP, 3.83 WHIP, 15 saves, and an 18-7 record. Tampa Bay used Kittredge as an opener a time or two between 2018 and 2021, but he has pitched exclusively in relief since 2021.

Kittredge's best pitch is likely either his sinker or slider. He got batters to chase on 41.7% of his pitches, meaning a lot of bad swings occurred against him. He doesn't walk batters, he doesn't allow hard contact, and the blueprint for success for the righty is there. Kittredge is now over 2 years removed from his Tommy John surgery; any rust he may have had last season has been washed off.

This spring, Kittredge has pitched 4 innings. He has struck out 3 batters, walked 1, given up just 1 hit, and he has yet to give up a run. Seeing Kittredge succeed in spring assuages any concerns fans, reporters, or coaches may have had about the right-handed reliever. Andrew will slot in toward the back of the bullpen mix, so it is vital that he maintains strong walk rates while limiting damage against him.

Keynan Middleton

Keynan Middleton was signed to a 1-year deal with a club option late in the offseason. The Cardinals signed him in hopes of bolstering the late innings of games and to provide high-leverage assistance. St. Louis will be Middleton's 6th organization since his induction to the league; he most recently saw time with the New York Yankees after a trade from the Chicago White Sox at the trade deadline.

Middleton has tallied just 15 saves in his career, but he has a 3.84 ERA, 4.47 FIP, 1.343 WHIP, and 9.2 K/9 in 194.1 career innings pitched. Batters have slashed just .225/.302/.355 against him in high-leverage situations for his career. It is likely he fills a late-inning role as well for the team. Middleton, Kittredge, Helsley, Romero, and Gallegos make for a potent collection of high-leverage relievers in a bullpen that needed some assistance.

Middleton does struggle with walks (10.8% in 2023), but he was in the top 9% of the league in strikeout rate last year. Middleton's best pitch has historically been his changeup, and it generates whiffs at a 37.7% clip. His fastball is used as his put-away pitch. Middleton also employs a slider.

In 3 innings this spring, Middleton has logged 2 strikeouts, giving up 2 hits, and has 1 hold to his name. He hasn't walked a batter yet either. If Middleton can continue to strike out batters at a high rate while working to limit his walks, he could become a strong weapon for Oli Marmol in high-leverage situations.