During the first half of the season, much of the blame for the St. Louis Cardinals’ struggles was placed on the front office for its inability to find depth. There is certainly a case to be made that if the Cardinals had better depth, then they would likely have improved upon their 44-46 first half record.
As the season has progressed the Cardinals depth has improved. Edmundo Sosa has been good all season, Lars Nootbaar has established himself as the fourth outfielder when Dylan Carlson is healthy, and some dumpster diving has improved the bullpen and made it less reliant on the big three of Giovanny Gallegos, Alex Reyes, and Genesis Cabrera.
This depth has allowed the Cardinals to handle injuries without missing a beat as Nootbaar has been able to step in for Carlson, and pitchers like Luis Garcia, TJ McFarland, Wade LeBlanc, and J.A. Happ have all solidified a pitching staff struggling with injuries.
Sosa and Nootbaar have combined for 1.3 fWAR in 289 plate appearances. All the other non-starters who have seen action this season have combined for -2.5 fWAR. Matt Carpenter and Jose Rondon are the only other bench players who have even been replacement level this year. The worst bench players have been Justin Williams (-0.8 fWAR), Andrew Knizner (-0.7 fWAR), and Lane Thomas (-0.4 fWAR).
It is obvious that the Cardinals struggled to find a fourth outfielder earlier in the season. They tried Williams, Thomas, and Scott Hurst, while even giving Tommy Edman and Jose Rondon time in the outfield. Nootbaar has finally solidified the fourth outfield spot, but the Cardinals likely cost themselves a couple wins by not finding him until August. Nootbaar was promoted before August, but he only made six plate appearances in June and three in July.
By basically waiting until August to find a fourth outfielder, the Cardinals cost themselves wins. The same could be said about waiting to fortify the pitching staff until July. McFarland, Garcia, LeBlanc, and Happ have all been great acquisitions, but how much better off would this team be if it had players like that at the beginning of the season?
It is obviously difficult to handle injuries to so many key players (Jack Flaherty, Miles Mikolas, Kwang-Hyun Kim, Harrison Bader, etc.), but the Cardinals did not have enough depth to fall back on when the injuries happened. Since improving their depth, the Cardinals have been able to handle the injuries to Dylan Carlson, Kwang-Hyun Kim, Ryan Helsley, and Wade LeBlanc. Since Carlson got hurt, the team has gone 5-4. Since Kim has been hurt, the team has gone 8-4. The improved depth has allowed the team to handle injuries and play good baseball at less than full strength.
If the team had built up this depth at the beginning of the season, then it would likely have better than a 4.3% chance at making the playoffs.
The Cardinals were clearly hoping that someone would step up in the outfield. Both Justin Williams and Lane Thomas had some promise, and the team was likely hoping that one of them would become a contributor. It was the same story in the bullpen with pitchers like Junior Fernandez, Seth Elledge, Ryan Helsley and Kodi Whitley all showing promise and being expected to deliver on that promise. In the rotation, it was thought that Carlos Martinez, John Gant, Johan Oviedo, Daniel Ponce de Leon, and Jake Woodford would be enough depth to keep the rotation strong.
The pitching staff struggled, though, as no one was able to establish himself. The Cardinals got over 213 innings from Johan Oviedo, Seth Elledge, Kodi Whitley, Junior Fernandez, Andrew Miller, Tyler Webb, Jake Woodford, and Daniel Ponce de Leon so far this season. This group has combined for -0.9 fWAR, with no individual being above 0.0. Luis Garcia, J.A. Happ, and TJ McFarland have already been worth 0.7 fWAR in just over 55 innings.
It is not a bad idea to leave a path to playing time for promising prospects. It is a bad idea to not have a plan B if they do not work out. Once these young players were unable to establish themselves, the Cardinals had no options to replace them. Then, once the injuries began to pile up, they were handed larger roles.
None of the players that the Cardinals were counting on were proven players in the roles that they were being given. If there had been more depth, then the Cardinals would have been able to guard against under-performance while still leaving a path to playing time if the younger players impressed.
The emergence of Sosa and Nootbaar mean that this problem will be limited next year, but the Cardinals will still need to figure out the bullpen and fill out the bench (a new starting middle infielder would help with this). The team did a great job of finding talent at a low price during the season, but if this had happened earlier, the Cardinals would almost certainly be in the thick of the playoff race instead of 4.5 games behind the Reds for the second wild card spot.