Giants manager Weiss stacks lineup with right-handed hitters vs. Marlins RHP Eury Perez

Giants manager Weiss is stacking his lineup with right-handed hitters for tonight's game against Miami Marlins right-hander Eury Perez, with left-handed bats Jarvis and Yazstremski sitting, per Mark Bowman.

What happened

The decision, reported by Bowman, is a direct response to a pronounced split in Perez's numbers against left- and right-handed hitters. Per Bowman, left-handed hitters carry a .592 OPS against Perez, while right-handed hitters have posted a .731 OPS — a gap wide enough to make the lineup construction essentially self-explanatory. Weiss, it appears, read the same scouting sheet you would have.

The more granular detail is the changeup. Per Bowman, left-handed hitters are hitting .120 with a .120 slugging percentage against Perez's changeup — a pitch that, by those numbers, functions less like an offering and more like a polite request to return to the dugout. The reason right-handed hitters don't see it as often, per Bowman, is that they have feasted on it when they do. So Perez largely keeps it away from them, which means a lineup built around right-handed bats both exploits the OPS gap and, in theory, forces Perez to work without his most dominant weapon against the side of the plate he's actually facing.

Why it matters

Lineup construction driven by opponent splits is one of the more legible in-game levers a manager pulls, and this one has unusually clean data behind it. The .592-versus-.731 OPS gap gives Weiss a concrete reason to sit two regulars, and the changeup numbers against left-handed hitters — .120 average, .120 slugging — make the case even harder to argue with. When a single pitch produces that kind of suppression against one side of the plate, a manager who ignores it is the one with explaining to do.

Sitting Jarvis and Yazstremski is not a commentary on their value. Per Bowman's framing, it is a one-game tactical adjustment tied to a specific opponent's profile — the kind of move that tends to look either obvious or inspired depending entirely on the box score.

Is Yazstremski hurt?

Per Bowman's report, Yazstremski is sitting for tactical reasons. The framing is explicitly driven by Perez's splits against left-handed hitters. Nothing in the report suggests a health concern.

The numbers

The split figures Bowman cites are worth sitting with for a moment. A .592 OPS against left-handed hitters and a .731 OPS against right-handed hitters is a meaningful gap — not a rounding error, not a small-sample curiosity. The changeup data sharpens it further: .120 average and .120 slugging for left-handed hitters against that pitch is the kind of line that makes a pitch look less like a changeup and more like a philosophical argument for going home early.

The fact that Perez rarely throws the changeup to right-handed hitters — because, per Bowman, they have hit it well when he does — adds a layer of strategic texture. A lineup of right-handed bats does not just exploit the OPS gap; it also puts Perez in a position where his best strikeout weapon is largely off the table against the hitters he is actually facing.

Where the club stands

The Giants enter this game at 65-97 (.401), sitting fourth in the NL West, 35 games back in the division. They have also been eliminated from the Wild Card race, ranking 11th with a figure of 23.0 relative to the cut line. San Francisco has dropped five straight.

None of that context makes tonight's lineup decision less interesting — if anything, it makes it more so. A club playing out the string still has reasons to develop information, test opponent-split theories, and give players meaningful at-bats in competitive situations. A right-handed-heavy lineup against a pitcher with a documented left-handed-hitter split is exactly the kind of low-cost, high-information exercise that makes late-season baseball worth watching even when the standings have long since moved on.

Looking ahead, the Giants are scheduled to travel to Globe Life Field on Wednesday, August 5, where Carson Whisenhunt is the probable starter against Texas's Cody Bradford. They return to Oracle Park on Friday, August 7, with JT Brubaker lined up against Detroit's Keider Montero, followed by Landen Roupp against Jackson Jobe on Saturday, August 8.

What we don't know yet

Bowman's report does not specify which right-handed hitters fill the lineup beyond the framing that Jarvis and Yazstremski are out. The full construction — who bats where, who absorbs the at-bats those two would have seen — is not detailed in the report.

It is also worth noting that the .731 OPS right-handed hitters have posted against Perez is a historical split, not a guarantee. Lineup construction improves the odds at the margins; it does not rewrite them.

What to watch

The changeup is the thread to pull. Per Bowman, Perez rarely throws it to right-handed hitters because they have hit it well. Watch whether that holds tonight — whether a lineup built specifically to exploit his splits forces him into uncomfortable counts, or whether Perez finds ways to neutralize the construction with his other offerings.

Also worth monitoring is how Weiss manages the at-bats for whoever fills the spots vacated by Jarvis and Yazstremski. In a season where the standings have been settled for some time, lineup decisions like this one carry a secondary purpose: they tell you something about how the organization is thinking about its personnel. A right-handed hitter who performs well against a pitcher with Perez's profile is a data point. Several of them, across several games, start to look like something more.

Tonight's game is the story. The lineup card is already written.