Four best-of-three series start today, all at the higher seed’s ballpark. It’s the shortest, swingiest round of October: one good start, one mistake in the field, one bullpen wobble can flip a whole series. Here’s what matters.

American League

Tigers at Guardians
Cleveland’s formula is familiar: strikes, infield defence and quick hooks if traffic appears. Detroit bring more thump than they have in years and enough run prevention to keep this tight. The first trip through the order will tell you plenty; if the Tigers win the zone early, their offence travels. Cleveland’s edge is in the late innings, where they can stack ground balls and shorten games.

Red Sox at Yankees
Compressed rivalry, different shape. New York lean on star power and leverage relievers; Boston’s contact and cutter-heavy staff make you win long at-bats. Watch how the Yankees’ right-handed bats handle elevated velocity and sweepers, and whether Boston can keep the ball in the park in the middle frames. One defensive play or one hanging breaker may separate it.

National League

Padres at Cubs
San Diego arrive with a high-end top of the roster; Chicago counter with strike-throwing starters, a deep bench and an outfield that can turn doubles into fly-outs when they’re right. Wrigley can turn on the wind and reward teams that catch the ball. Expect both managers to push matchup buttons early; a pinch-hit in the sixth could be the swing.

Reds at Dodgers
Speed and youth against a club that’s been here a thousand times. Cincinnati’s best path is pressure: take extra 90s, make Los Angeles execute throws and turn the middle innings into a track meet. The Dodgers’ route is the opposite: control the zone, win 0-0 counts, and let their length through the lineup create a crooked number. If this stays low-scoring into the seventh, the Dodgers’ leverage plan is an advantage.

What decides best-of-three

• First innings matter more than usual. A two-run first can dictate bullpen usage for an entire series.
• Leverage relievers will appear as early as the fifth if traffic and the lineup card demand it.
• The third starter is often the secret weapon out of the pen; whoever gets nine outs from that role without damage usually moves on.
• Running games matter. Extra 90s turn singles into rallies in this format.
• Defence is a separator. One infield play made or missed is often worth a win.

Format and cadence

All series are best-of-three, all games at the higher seed’s park, with staggered first pitches across afternoon and evening. Win two and you’re through to an off-day and a reset rotation; lose the opener and every decision becomes a leverage decision.