MLB Insider: Why the Red Sox should not trade for Nolan Arenado

I’ve seen the Nolan Arenado and Boston Red Sox connection. I’ve thought about it and sat on it. And I have not wavered in my thinking that it’s a move that Boston should not make.

At the start of the offseason, Arenado made it clear that he wanted a trade out of St. Lous. The Cardinals signaled they were very open to moving the star third baseman, who is owed $74 million across the next three seasons. And all offseason, a trade has seemed more likely than not.

It started with a trade involving the Houston Astros, which Arenado nixed. The Astros then pivoted to free-agent infielder Christian Walker, taking them out of the Arenado sweepstakes. It’s left Arenado’s market uncertain and, in the words of Katie Woo of The Athletic, with “the Red Sox representing Arenado’s last chance to get dealt before the 2025 season.”

So why should the Red Sox not trade for Arenado?

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Why a Nolan Arenado trade makes no sense for the Red Sox

Let’s look at the Red Sox’s infield. Rafael Devers is entrenched at third base and has indicated that he does not want to move off the position in 2025 and beyond. Arenado has indicated a willingness to switch positions as part of a trade, and the most obvious fit besides third base would be at first base.

But the Red Sox have young slugger Triston Casas at the position. There have been trade rumors surrounding Casas this offseason, but moving on from a player as talented as Casas would be incredibly difficult. He’s only 24 years old, isn’t a free agent until 2029, and has 40+ homer power, according to numerous scouts.

The only argument that can be made for moving Casas is that it would significantly improve the Red Sox’s pitching staff. A name that has been linked to Boston is Seattle Mariners right-hander Luis Castillo, but Boston should demand a higher-level and cheaper option than Castillo if it were to consider moving on from Casas.

Even then, moving on from Casas should be a non-starter for the Red Sox. He’s too talented and valuable to part with.

The other side of the equation is that Arenado is not the same player he was with the Colorado Rockies, where he established himself as baseball’s premier third baseman. Now, Arenado is coming off one of his worst seasons as a pro. His 16 homers were his least since 2014. His .719 OPS was his lowest since 2013. His .394 slugging percentage was the lowest of his career. He still posted a 101 OPS+, meaning he’s just about league average as a player.

Moving Casas is not something that the Red Sox should do. But moving Casas, and then potentially replacing him with the 34-year-old Arenado and the $74 million remaining on his contract, would be organizational malpractice and could set the franchise back years.

Craig Breslow, the Red Sox’s lead executive, can’t do it. And I don’t expect him to.