The Arizona Diamondbacks are slowly fading out of the playoff race. With that happening, the team has some decisions to make at the MLB trade deadline. The Diamondbacks have a few key contributors nearing free agency, and those players can generate a high return should Arizona choose to sell.

The Diamondbacks have not declared whether or not they would be buyers or sellers at the deadline. One thing for certain is Arizona would love to be buyers if they can. Now, they have to start winning more games if they are going to go all-in on this season. However, realistically, the Diamondbacks have a chance to build their team for the future by making some trades this season and acquiring top prospects.

Unless there is a contract extension happening in the near future, Arizona is going to lose Zac Gallen, Eugenio Suarez, Josh Naylor, Merrill Kelly, and Jalen Beeks. These are all players that teams should be interested in as the trade deadline inches closer. The only question is which player will be dealt first, and how big will the return be?

Below we are predicting the next big trade the Diamondbacks will make this season.

The next big trade should be Zac Gallen

Zac Gallen is having a career-worst year this season, but that should not deter teams from taking a chance on him at the deadline. In addition, his 2025 struggles are not going to make his price go down as much as one might think. The right-hander still has great stuff on the mound, and he started July off with his best start of the year.

Gallen will have one or two more starts before the MLB trade deadline, and the Diamondbacks will need him to be lights out. Of course the team wants to win, but Arizona would be able to up the price on him if he continues to pitch well.

There are many teams that need a solid starting pitcher in order to make a run in the playoffs. In the National League alone the NL Central teams and New York Mets come to mind. It will come down to which contending team is willing to give up some prospects for half a year of Zac Gallen.

What can the Diamondbacks get in return?

As mentioned, the Diamondbacks are going to get plenty of good prospects this trade deadline should they decide to sell. Gallen himself will demand a few top prospects. This season is not an indication of his skill, and the entire MLB knows that.

As for who the Diamondbacks might get in return, that all depends. It is highly unlikely that Arizona will get a No. 1-5 prospect from a team. However, acquiring a few different prospects in the top 30 list is more than realistic. The team could some talent on the mound, and may on the corners of the infield considering both of those players are free agents at the end of the year.

The Diamondbacks are close to being contenders. Late season runs happen all the time. We saw it happen last year with the Detroit Tigers, and in 2023 when Arizona went to the Word Series. However, with so many players at the end of their contract, the Diamondbacks would be smart to sell at the deadline and build for a better future.