Best Ball Flex Spot Strategy: How to Fill Your Flex Spots in Best Ball Drafts
The optimizer handles your lineup decisions each week — your job is to draft the roster. That means flex decisions are made during the draft, not during the season. Build your roster to have strong flex competition at each position so the optimizer has high-quality options across the board.
Flex Spot Quick Reference
| Flex allocation scenario | Best ball impact | Draft action | Mistake to avoid |
|---|---|---|---|
| WR-heavy flex (flex goes to WR depth) | Higher consistent weekly floors — WR target volume is more week-to-week stable than RB carry volume | Default approach: prioritize WR depth in flex slots | Abandoning WR-heavy flex because a few RBs fall late — late-round RBs can fill flex, but your core strategy should be WR-heavy |
| RB-heavy flex (flex goes to RB depth) | Higher weekly variance — when elite RBs are undervalued at ADP, filling flex with RBs produces outsized returns | Shift to RB-heavy flex only when RBs are clearly falling relative to ADP | Mechanically applying WR-heavy flex without checking if RBs are undervalued at your specific picks — the best strategy responds to how the draft unfolds |
| Second TE in flex | Viable only if the second TE has consistent target share (15%+) and floors that compete with WR3/RB3 options | Target a second TE in the flex only if he falls significantly below his expected ADP | Carrying a boom-bust TE with 8% target share in your flex — he wastes the optimizer’s decision-making by scoring 0–5 points most weeks |
| Flex as variance lever | The flex is where you introduce targeted variance — a high-upside RB or WR whose ceiling is higher than his competition but who may produce nothing | Use the flex to intentionally increase ceiling for tournament-style contests | Using all flex spots as safe floor plays — in best ball tournaments, ceiling is required to win; the flex spot is where you add it |
| Superflex formats | Superflex best ball formats add a second QB slot in the flex — completely changes the draft strategy (draft 2–3 QBs, not 1–2) | In superflex, treat the flex as a QB slot until QB value falls below skill position value at your pick | Applying 1QB flex logic to a superflex format — the second QB slot in superflex changes every position’s ADP |
| Tracking flex utilization post-draft | The optimizer maximizes flex utilization automatically — do not manually override the optimizer if it selects an unexpected player | Trust the optimizer; it is processing all possible lineup combinations, not just the obvious ones | Second-guessing the optimizer when it starts your flex over a player you expected — the optimizer has information about the full roster you do not |
WR-Heavy vs RB-Heavy Flex Allocation
WR-heavy flex strategy. Allocate your flex spots primarily to WRs. In best ball, WRs have higher average weekly ceilings because their target volume is more consistent week to week than RB carry volume. WR-heavy rosters win best ball tournaments more often because WRs produce more reliable weekly output for the optimizer to select from.
RB-heavy flex strategy. Allocate your flex spots primarily to RBs. This works when the RBs available at your draft picks are undervalued relative to their actual weekly upside. In a draft where elite RBs are falling, filling the flex with RBs can be highly profitable.
TE Flex Consideration
Only take a second TE in the flex if he is a high-floor option. A second TE in your flex makes sense only if that player has consistent target share (15%+) and weekly scoring floors that compete with WR3 and RB3 options. A low-floor, boom-bust TE in your flex wastes the optimizer’s options.
For how flex spot decisions connect to overall roster construction, see: Best Ball Draft Strategy: How to Build the Best Roster in Best Ball Fantasy Drafts.