End of the Nolan Arenado era: Grading 2 trades, his performance, and Cardinals' run

The St. Louis Cardinals put an end to Nolan Arenado's time with the organization recently, trading the future Hall of Fame third baseman to the Arizona Diamondbacks as they clear the way for their rebuild to go into full motion.

While much of the coverage and attention has (rightfully) focused on what this means for the Cardinals in 2026 and beyond, I don't want to move too far past this deal without taking a hard look at how Arenado's time with the Cardinals actually went.

As I began to ponder that, I quickly realized how complicated assigning a singular grade to that would be. There are really four major storylines that need to be looked at and examined by Cardinals fans: the initial trade to acquire Arenado from the Rockies, Arenado's individual performance as a Cardinal, the success the Cardinals had on the field while Arenado was with the club and how he contributed to that, and how we are viewing the trade of Arenado to the Diamondbacks.

I asked fans over on X how they would grade these subjects, and now I'm going to give an in-depth evaluation to each of them from my perspective as well.

Grading the Cardinals' Nolan Arenado trades, his performance as a Cardinal, and the team's on-field success during his time with St. Louis

Grade for Cardinals' trade for Nolan Arenado in 2021: B

Originally, I had the initial trade for Arenado still graded as an A for St. Louis, but as I've looked deeper into the value he gave to the Cardinals during his time here, the grade actually lowered.

In a vacuum, this was still an excellent move by the Cardinals front office. We'll get into Arenado's performance on the field and the Cardinals' team success (or lack thereof) in a moment, but looking purely at the value the Cardinals had to give up to get Arenado, it was a slam-dunk move.

On February 1st, 2021, the Cardinals traded Tony Locey, Elehuris Montero, Mateo Gil, and Jake Sommers, along with Austin Gomber, in exchange for Nolan Arenado and $50 million in cash. Gil, Locey, and Sommers never ended up playing in the big leagues, Montero was a -2.6 fWAR player with Colorado, and Gomber put up just 4 fWAR in his five seasons pitching with the Rockies.

The Cardinals, on the other hand, acquired Arenado to be a superstar third baseman for them, and while he only lived up to that billing occasionally, he still produced 18.3 fWAR during his time with St. Louis, while the Rockies ended up with a net 1.4 fWAR in total value.

While that shows us the distance in how much the on-field value the Cardinals acquired in this trade by netting Arenado, the financial ramifications of this trade matter a ton, and you have to factor that in when valuing the trade as a whole.

During Arenado's time with St. Louis, he produced approximately $146.1 million in value on the field according to FanGraph's "Dollars" stat, which converts fWAR into a player's dollar value. While that is a ton of on-field value, it is also important to point out that the Cardinals are on the hook for $153 million of Arenado's contract between the years he played in St. Louis and the money they sent to the Diamondbacks in the trade. That technically means that the Cardinals overpaid for Arenado in terms of financial value, and it is far too early to know if the prospect they got in return for Arenado will even get to the big league level, let alone produce positive value there.

That part matters. If Arenado was still valuable enough to net the Cardinals good prospects in return and/or not require St. Louis to eat as much money on the deal, the trade for him likely still ends up as an "A" because he also brought them back nice value on his way out. Martinez is about as complete an unknown of a prospect as you can get, so I'm not going to assign much future value to him yet.

Let's recap. The Cardinals gave up virtually nothing to acquire Arenado, so that was an A+ effort. Arenado was paid to be a superstar, though, and that only happened for the first two years of his time with St. Louis (and mainly the 2022 season). Had he not cratered in 2025 or had a bit better of a season in 2023 or 2024, his production would have better matched the money he was being paid. But the Cardinals did commit superstar money to Arenado, and he did not live up to that billing often enough.

Overall, I grade the trade for Arenado as a "B" given how his time in St. Louis panned out. If Jack Martinez ends up having a decent big league career, that could change this grade a bit.

Grade for Nolan Arenado's performance as a Cardinal: C

This was difficult to grade. When it comes to what you would have hoped from and honestly expected from Arenado as a Cardinal, the grade is probably more like a D, but when you actually look at his performance on the field given the stage of his career and the money the Cardinals paid him, I'd say it was a pretty average tenure on the field.

In Arenado's debut season for the Cardinals in 2021, he posted a .255/.312/.494 slash line with 34 home runs and 105 RBI, posting 4.3 fWAR in 157 games, and was named to the NL All-Star team while winning a Gold Glove and the Platinum Glove. His 112 wRC+ was the lowest of his career since his second full big league season, but it was still good enough, paired with elite defense, to be worth about $34.1 million in FanGraphs' "Dollars," so I'd say that was a really good season.

2022 was by far his peak with St. Louis, as Arenado was worth $57.7 million en route to a 7.2 fWAR season, a top-3 MVP finish, and his sixth straight Platinum Glove to go alongside his Gold Glove and Silver Slugger that season. Had his teammate Paul Goldschmidt not won MVP, Arenado may have secured the award instead. Arenado finished that year with a .293/.358/.533 slash line, slugging 30 home runs and driving in 103 runs in 148 games.

What put a bit of a damper on his season, though, was the lack of production in the NL Wild Card series. After going 0-4 in the one-game playoff with the Los Angeles Dodgers in 2021, Arenado followed that up with a 1-8 performance against the Philadelphia Phillies in 2022, scoring one run and driving in zero as the Cardinals were swept by Philadelphia.

2023 and 2024 ended up being "fine" years for Arenado, posting a 2.7 fWAR and 3.2 fWAR respectively in those two campaigns as the Cardinals crumbled in 2023 and were mediocre in 2024. 2025 was a train wreck for Arenado, as he slashed just .237/.289/.377 with 12 home runs and 52 RBI in 107 games played.

Overall, Arenado had one excellent season in 2022, a very good season in 2021, "fine" years in 2023 and 2024, and a massive failure in 2025. Given how he was being paid to perform, I would say it was a "C" tenure overall on the field. He could have done a lot more for the Cardinals, but he also wasn't the reason they crumbled.

Grade for Cardinals' run as a team while they had Nolan Arenado: D-

This one was fairly easy for me. The Cardinals did make the playoffs twice with Arenado in uniform and had a great year in 2022 that ended in unceremonious fashion, so I think that does save them from an "F" grade. But everything else was awful compared to what fans, media, and, honestly, the Cardinals expected.

The Cardinals not only failed to advance in the playoffs a single time with Arenado, but they failed to win a single playoff game. Arenado at least managed to win one playoff game with the Rockies...yikes.

On top of that, it's hard to argue against the fact that the Cardinals had one of the worst stretches in franchise history to end Arenado's tenure from 2023-2025, finishing with a 232-254 record (.477 win%) over that period of time. When the Cardinals acquired Arenado to pair with Goldschmidt, no one would have believed you if you said it would go this poorly.

Grade for Cardinals trade of Nolan Arenado to the Diamondbacks: C

Ultimately, the Cardinals' hands were tied when it came to offloading Arenado this offseason. Mozeliak reportedly had a much better deal in place with the Astros last offseason that Arenado said no to, and the Boston Red Sox ended up getting Alex Bregman, sticking St. Louis with Arenado for another year. This offseason, Arenado said no to the Athletics, who actually would have taken on more of Arenado's contract, but the Cardinals cannot control that. They did get him to waive his no-trade clause for Arizona, though, which was a huge win, especially with the Padres wanting to acquire him but offering even less money to make the deal happen.

Considering how poorly Arenado has played as of late, the Cardinals were not going to get a solid prospect return for him, and they were likely going to need to eat a lot of money to make the deal happen. Even then, some still doubted if Bloom could even pull that off, so a C grade here seems fitting.

Overall, it's still incredibly frustrating how empty the Arenado era in St. Louis ended up becoming. I still had a ton of fun watching him with the Cardinals, but by the end, all parties wanted this to be over, and there were just not enough highs, both from Arenado himself and from the organization, to call this a successful partnership. It was fine, but considering what could have been, it feels like a massive disappointment.