Best MLB runs matchups — Friday, September 4, 2026

Frequently asked questions

Who has the best runs matchup today (Friday, September 4, 2026)?

Randy Arozarena (SEA) — top of the board at 100, facing RHP Kade Morris. A strong bat into a beatable arm is what pushes it to No. 1.

What are the best MLB runs matchups today (Friday, September 4, 2026)?

The top runs matchups on Friday, September 4, 2026: Randy Arozarena (100), Yordan Alvarez (100), Pete Crow-Armstrong (97), Alec Burleson (96), Sam Antonacci (96). The full board ranks every hitter in every game by runs upside.

Did the top runs matchup get a run on Friday, September 4, 2026?

Yes — Randy Arozarena got 1 run.

Which hitters have a platoon edge today?

Yordan Alvarez (HOU) — lefty bat vs RHP, .165 against righties this year. Pete Crow-Armstrong (CHC) — lefty bat vs RHP, .174 against righties this year. Alec Burleson (STL) — lefty bat vs RHP, .143 against righties this year. Sam Antonacci (CWS) — lefty bat vs RHP, .157 against righties this year. Jake Bauers (MIL) — lefty bat vs RHP, .172 against righties this year.

How is the runs matchup score calculated?

It reads how often he scores against that hand, weighted to recent form, then asks how good the bats behind him are at bringing him home. Spot in the order matters more here than almost anywhere. Then the bullpen, park and weather. 0–100 across the slate.

What does R/PA mean?

It's the share of a hitter's plate appearances that end with him scoring a run. Around .117 is league average. Runs depend on getting on base and the bats behind you, so lineup spot and team context matter as much as the individual.

What does the score actually mean?

Higher is better. Runs scored is a team stat wearing one player's name — the top of the order in a good spot will out-grade a better hitter batting seventh, because he gets more trips and more help.

What's the confidence meter?

It's how much data is behind the call — sample size on both the hitter and the pitcher, plus whether the lineup's official. A high score with low confidence is a thinner read than the same score backed by a deep track record. It's not a probability of a run.

What is a platoon split (handedness split)?

Same idea as the other contact boards, with one wrinkle: scoring a run starts with reaching base. The score leans on his rate against today's hand, then asks whether the bats behind him can bring him around.

What are park factors?

A park that gives up hits gives up runs. Gaps, altitude, and weather all raise the odds a leadoff single turns into a crossed plate. Above 1.00 bumps the score, below 1.00 trims it.

What do "2W", "SZN" and "2Y" mean?

The timeframes behind each rate: the last two weeks (recent form), the current season, and a trailing two years (a stable baseline). Recent form counts most, and small samples get pulled toward league average so a hot week doesn't fool the model.

What do "≈ est", "Due" and "Not starting" mean?

"≈ est" is a hitter we don't have splits for yet — a rookie or unmatched ID — shown at a league-baseline estimate instead of dropped. "Due" means he hasn't recorded a run in a while and profiles for regression. "Not starting" means he was projected but didn't make the official lineup, so he slides to the bottom where you can still look him up.

Can I use this for runs props or DFS?

That's what it's built for — pre-slate research. The board surfaces which hitters have the best conditions today, and where one exists, we show the book's "1+ run" line so you can shop the price. We're not a sportsbook and we don't post picks — we show the matchup data, the line, and the result. (Best-price and all-book odds are a Pro feature.)

How accurate is the model?

We grade every board against the box score. Runs scored leans on teammates, so the top of this board out-hits the slate by a smaller margin than the pure-contact boards do — the posted season rate shows exactly how much.

When do lineups update?

Projected lineups (marked "Proj") come from each team's last game. Official lineups usually drop about two hours before first pitch, and the board updates itself as they post. Batting order is a big driver, so it's worth a second look mid-afternoon — rankings shift as lineups lock.

Is MatchWiz free?

Yes. The full board, every game page, and the daily archive are free, no login. Best-price odds and the betting tools are the paid tier.