SF Giants are trying to upgrade major weakness from 2025 season with latest moves

On Friday, the SF Giants completed a trade to acquire outfielder Joey Wiemer from the Miami Marlins. The move is the second outfield addition of the offseason, and the second time they have added someone with quality defense.

SF Giants are trying to upgrade major weakness from 2025 season with latest moves

The Giants finished in last place with -18 Outs Above Average (OAA) in 2025. Since the start of 2022, they sit comfortably in last place among outfield defenses with -74 OAA. This is an issue that has spanned multiple seasons.

As of right now, the Giants plan to return two of those outfielders in Heliot Ramos and Jung Hoo Lee. Ramos and Lee were near the bottom in outfield defense in left field and center field, respectively. Ramos put up -9 OAA, whereas Lee posted -5 OAA.

The Giants have highlighted outfield defense as an area to improve this offseason. That said, the improvement may need to come internally. They believe that Ramos and Lee's defense can be improved through coaching. To some degree, that may be the case.

In the meantime, they are making moves to improve outfield defense around the margins. Justin Dean and Joey Wiemer's best trait just might be defense. Dean has only played in a handful of games during his major league career, so the defense is still is small sample territory. He does not offer much offensively, but he is fast and a good baserunner. Speed is critical to being a good outfielder. Some players can get by without it, and those players usually have good instincts.

On the other hand, Wiemer has played quite a few games in the majors. He has graded out as an above-average glove in the corners, and a capable defender in center field.

As of right now, the Giants have 10 outfielders on the 40-man roster. That is a lot. If there is going to be turnover in any area of the roster, it will likely come from there.

The Giants have a lot of outfielders, but few have carved out a role with the club. Many of the options are below-average defenders, so they do not fit the description for a typical fourth outfielder. Those same options also do not hit enough to overlook the defensive issues.

This offseason, the Giants are trying to raise that defensive floor. Justin Dean and Joey Wiemer may not hit all that much. In the case of Wiemer, he does hit with occasional power. However, both have the traits to at least fill a reserve role, and it starts with defense.