Quick mini-guide for anyone betting MLB First Five Innings lines.

Most bettors glance at a team's bullpen ERA on a scoreboard graphic and use it to gauge risk if the starter gets pulled early. This is a mistake — bullpen ERA is a lagging, noisy, season-long number that tells you almost nothing about tonight's specific risk.

What actually matters for F5 betting:

1. 3-day rolling workload — how many pitches has the pen actually thrown recently? A "good" bullpen on paper that's been overworked the last 3 games is a real risk if your starter is a 5th-inning question mark.

2. Back-to-back usage flags — any reliever who's pitched in 2+ consecutive games should be discounted, regardless of his season stats.

3. Closer/setup availability — if the top leverage arms are gassed or unavailable, the replacement-level quality entering the 5th drops hard, and that's exactly the innings window F5 bets live in.

4. First-time-through-the-order splits for the starter — not season ERA. F5 outcomes are dominated by how a starter performs the first time through a lineup, which can differ meaningfully from his full-game numbers.

The market is slow to price bullpen fatigue into F5 lines specifically because it's a lower-volume, less-scrutinized market than full-game lines. That lag is where a lot of the value lives.

If you're serious about building a repeatable process around this instead of betting on gut feel, that's exactly what we do daily inside First Five Edge.