It is clear that the Cardinals struggled to receive production from the outfield in 2020. Tyler O’Neill did not take a step forward despite being the team’s starting left fielder, Dexter Fowler was below average, Harrison Bader had a hot streak which pushed his wRC+ to 113, and Dylan Carlson struggled after his initial promotion. Of these four, Carlson is clearly the most promising, and Fowler will likely leave the team in free agency following the 2021 season. Thus, when thinking about the Cardinals future outfielder, it is possible to pencil Carlson into a starting spot, and leave Fowler off the roster. This leaves two outfield positions open for O’Neill, Bader, and any external acquisitions that the Cardinals make. However, if the Cardinals actually want to improve their lineup in the future, they cannot afford to start both Bader and O’Neill, unless one or both of them can become consistently above league average hitters.
Tyler O’Neill has always shown plenty of raw power, but he has never been able to consistently tap into it. The main problem with him has been an inability to make consistent contact, and that has limited his overall offensive production. However, in 2020, O’Neill actually improved in that aspect, but he also had the worst offensive season of his MLB career. In 2020, O’Neill slashed his strikeout rate from 35.1% to 27.4% while also walking more (6.6% walk rate in 2019, 9.6% in 2020) and cutting his whiff rate from 41.4% to 33.9%. All of these are positive signs for O’Neill, and they are definitely improvements that he needed to make if he wants to hold down a starting job. However, while he improved his plate discipline, he contact results got worse as he posted a career worst xwOBA (.280) and average exit velocity (88 mph).
If O’Neill is going to be an effective hitter, then he needs to be able to take pitches and not swing and miss as much, while also being able to consistently hit the ball with power. He has never been able to do both at the same time, and given the improvements that he made with his plate discipline in 2020, the Cardinals may be willing to give him another season to see if he can figure it out. However, if he does not improve, then he is simply a great defender with plenty of speed and a limited hitting ability. If he could improve at the plate, at least to the point of respectability, then he would likely have a role in the outfield locked down. However, the problem is that Harrison Bader has nearly the same profile.
Bader is also fast, and an excellent defender who struggles with strikeouts (32% strikeout rate in 2020). The differences between Bader and O’Neill at the plate are that Bader takes more walks (11.3% walk rate in 2019, 10.4% in 2020) and O’Neill has more raw power. However, in terms of career production, these difference are marginal as Bader is averaging a 95 wRC+ and O’Neill is averaging a 91 wRC+. If these numbers do not improve, then the Cardinals lineup will always be limited if they are playing together.
Therefore, unless one or both of them improve and become an an above average hitter, the Cardinals may need to choose one to keep and one to trade. There is certainly value in keeping one of them as a strong defensive player who can use his speed as a threat, but the Cardinals must also find an outfielder that can be a solid hitter if neither of them can develop into this role.
The Cardinals will likely give a large amount of plate appearances to each of them next season in order to save money. However, this might not be the right decision. It is possible that one of them develops into a consistently solid hitter, especially as both of them took strides this year. However, each of them has clear flaws and it is difficult to project them becoming consistently dangerous hitters. Therefore, the Cardinals should consider trading one of them this offseason while they still have trade value. Another down season as the plate from O’Neill next season would likely eliminate any trade value that he once had while a down season for Bader next year would definitely make him less attractive of a trade candidate.
If the Cardinals could get a decent player for one of them, then it could help the Cardinals look into potential alternatives for the 2021 season, while also preparing a spot in the outfield for an acquisition after the 2021 season. At this point, Bader has a much stronger track record of success than O’Neill and is likely the safer bet to become a better player. Thus, if there is any kind of a market for Tyler O’Neill this offseason, the Cardinals should explore it and see if they can turn him into a potentially more useful piece. Then, the Cardinals could have a starting outfield of Carlson, Bader, and Fowler next season and when Fowler’s contract comes off the books, they would have a spot in the lineup that could be filled by a strong hitter.
This would allow the Cardinals to save money this year, which is what they are trying to do, get a decent return for O’Neill, and prepare the outfield for the future. However, regardless of what the team does, one thing is clear: the Cardinals can not start two below average hitters in the outfield and expect to be successful.