SF Giants signing Luis Arraez spells trouble for pair of young infielders

With news that the SF Giants have reportedly signed three-time batting champ Luis Arraez to a one-year, $12 million deal, the team is getting one of the best contact hitters in the game. Yet, adding him will greatly impact two other infielders on the team in Casey Schmitt and Christian Koss.

It’s no secret that the Giants have been looking to upgrade at second base this offseason. They have been connected to trade targets like Brendan Donovan of the St. Louis Cardinals and Nico Hoerner of the Chicago Cubs but a trade never materialized.

What SF Giants signing Arraez means for Schmitt and Koss

It seems Arraez was a backup plan if trade talks didn’t pan out and he certainly matches the profile of the type of hitter president of baseball operations Buster Posey wants to see in the lineup. The Giants have a lot of hitters in their lineup who swing and miss a ton and strike out at a fairly high rate. Posey has emphasized putting the ball in play and Arraez excels at that as he rarely ever strikes out.

His defense leaves a lot to be desired at second base so it is an open question whether Arraez will really be an improvement over Schmitt, but for the time being let’s examine how this move will impact the second base depth chart.

Schmitt is now going to be a bench player and he figures to be a solid utility option. Last season he proved that he can play every infield position including first base which was a pleasant surprise. 

His hands and instincts allow him to be serviceable at any of those spots in the infield even though third base is where he excels but obviously there is a Matt Chapman-sized impediment to playing time there.

Schmitt became the starting second baseman last year after Tyler Fitzgerald’s struggles and acquitted himself quite well while slashing .237/.305/.401 with 12 home runs and 40 runs driven in. The Giants probably would have been fine if Schmitt was the starting second baseman entering 2026, but Arraez is certainly a superior hitter as he slashed .292/.327/.392 with with eight homers and 61 RBI in a relative down year. This move at the very least will strengthen San Francisco’s bench which is never a bad thing.

While Schmitt will now be a bench piece, Christian Koss may very well be the odd man out on the roster after this move. Koss was a surprise breakout performer last year in spring training and made the team out of camp over other options like Brett Wisely. Koss proved to be solid defensively at second base, third base, and shortstop and filled in very nicely when needed.

He proved to be a decent contact hitter for the team as well and had a respectable slash line of .264/.309/.368 with three homers and 23 runs batted in. 

It will be interesting to see if Koss will end up making the team out of spring training or not. The Giants could carry two infielders on the bench to begin the season. They did that last season with Schmitt and Koss so it is possible. However, that probably leaves room for just one outfielder and a catcher on the bench if they carry both and San Francisco may want to stick Luis Matos on the roster so they don’t lose him on waivers since he’s out of minor league options. 

Either way, if Koss begins the year with Sacramento or San Francisco, we will see him at some point in 2026. He did a lot of good things in 2025 and is a nifty player to have so this is not the end of Koss even if this signing costs him a roster spot to start the year. 

We’ll see if the Arraez signing proves to be a true upgrade at second base. For the time being Schmitt and Koss will be bumped down on the depth chart and will see less playing time but they are good insurance options to have if the veteran signing doesn’t work out as expected.