The San Francisco Giants should make defense the deciding factor at second base if Marcelo Mayer and Casey Schmitt project to provide similar offensive value.

The Giants already had evidence that the position could become a meaningful source of run prevention. Luis Arraez recorded 11 outs above average at second base during his time with the club in 2026, before adding one more with the Philadelphia Phillies.

An Oct. 24 McCovey Chronicles review renewed attention to that improvement. For San Francisco, the useful offseason lesson involved how to evaluate the players competing to replace those innings.

The decision should account for the entire job, including what happens when the ball is put in play.

Arráez Supplied a Defensive Benchmark

Arraez’s Statcast record separated his work with each team, an important distinction when assessing his completed campaign.

His 12 outs above average represented the combined total. Eleven came with the Giants, where his improvement added value beyond his established contact skills.

The recent review also credited infield coach Ron Washington’s work. That reporting supported a reason to examine instruction and preparation, although one player’s results could not establish exactly how much credit belonged to any particular factor.

For the team, the next step should be practical. Identify which positioning choices, footwork adjustments and preparation routines helped, then determine which lessons applied to other infielders.

Mayer and Schmitt would have their own strengths and limitations. Expecting either to duplicate Arraez’s measured improvement would be an unsupported projection.

The better standard would be consistent execution: cover the expected ground, complete routine plays and give the pitching staff dependable support. Those skills should receive deliberate evaluation alongside the offensive projections.

Give the Competition a Clear Test

The Giants’ current Opening Day projection left second base open to further assessment. Health and any offseason trade would influence the eventual choices.

Once medically cleared, the candidates should receive enough work at the position for coaches to evaluate their movement, throws and double-play exchanges. The team should combine those observations with its defensive information.

Mayer’s positional background gave San Francisco options, but versatility should not prevent it from identifying where he could provide the most value.

Schmitt’s ability to handle other assignments also should be evaluated within the complete infield plan. Moving him elsewhere would require a dependable second baseman behind that decision.

The proposed tiebreaker applies when the overall offensive projections are close. It would not mean ignoring a substantial difference at the plate.

The Giants needed to improve their pitching this winter. Choosing a second baseman who converted more of the staff’s playable contact into outs would support that investment, giving this competition a consequence beyond which hitter won more spring at-bats.