{"sport":"mlb","slug":"leon-kellman","bio":{"fullName":"Leon Kellman","position":"X","team":null,"heightInches":71,"weightLbs":160,"birthDate":"1918-07-11","rookieSeason":1946,"lastSeason":1948,"status":"RET","externalIds":{"mlbam":"818642","chadwick":"1e69dd82","retro":"kelll101"}},"draft":null,"statTables":[{"id":"batting","label":"Batting","columns":[{"key":"g"},{"key":"ab"},{"key":"r"},{"key":"h"},{"key":"doubles"},{"key":"triples"},{"key":"hr"},{"key":"rbi"},{"key":"sb"},{"key":"bb"},{"key":"so"},{"key":"avg"},{"key":"obp"},{"key":"slg"},{"key":"ops"}],"rows":[{"season":1946,"seasonType":"REG","team":"Cleveland Buckeyes","gamesPlayed":20,"values":{"g":20,"ab":62,"r":14,"h":20,"doubles":4,"triples":0,"hr":0,"rbi":11,"sb":3,"bb":11,"so":null,"avg":0.323,"obp":0.455,"slg":0.387,"ops":0.842},"rowScope":"team"},{"season":1947,"seasonType":"REG","team":"Cleveland Buckeyes","gamesPlayed":14,"values":{"g":14,"ab":40,"r":8,"h":11,"doubles":1,"triples":1,"hr":1,"rbi":9,"sb":0,"bb":7,"so":null,"avg":0.275,"obp":0.396,"slg":0.425,"ops":0.821},"rowScope":"team"},{"season":1948,"seasonType":"REG","team":"Cleveland Buckeyes","gamesPlayed":18,"values":{"g":18,"ab":61,"r":10,"h":17,"doubles":1,"triples":1,"hr":0,"rbi":7,"sb":3,"bb":11,"so":null,"avg":0.279,"obp":0.413,"slg":0.328,"ops":0.741},"rowScope":"team"}],"careerTotals":{"REG":{"g":52,"ab":163,"r":32,"h":48,"doubles":6,"triples":2,"hr":1,"rbi":27,"sb":6,"bb":29,"so":null,"avg":0.294,"obp":0.425,"slg":0.374,"ops":0.799}}},{"id":"advanced","label":"Advanced (League-Relative)","columns":[{"key":"ops_plus","label":"OPS+","description":"On-base plus slugging vs the player's own season+league (100 = league average). Park-unadjusted; OBP uses a consistent (H+BB)/(AB+BB) rate. Higher is better.","format":"int","higherIsBetter":true},{"key":"era_plus","label":"ERA+","description":"Earned-run average vs the player's own season+league (100 = league average). Park-unadjusted. Higher is better.","format":"int","higherIsBetter":true}],"rows":[{"season":1946,"seasonType":"REG","team":"Cleveland Buckeyes","values":{"ops_plus":148,"era_plus":null},"rowScope":"team"},{"season":1947,"seasonType":"REG","team":"Cleveland Buckeyes","values":{"ops_plus":128,"era_plus":null},"rowScope":"team"},{"season":1948,"seasonType":"REG","team":"Cleveland Buckeyes","values":{"ops_plus":101,"era_plus":null},"rowScope":"team"}],"careerTotals":{"REG":{"ops_plus":125,"era_plus":null}},"advancedMeta":{"method":"computed in-house from MLB StatsAPI season batting/pitching lines, normalized to each player's own (season, league) baseline","formulas":{"era_plus":"100 * lgERA / playerERA (league ERA = 9 * ΣER / ΣIP over the season+league)","ops_plus":"100 * (OBP/lgOBP + SLG/lgSLG - 1)","career_era_plus":"innings-weighted league ERA / career ERA (B-Ref method)","career_ops_plus":"AB-weighted OBP & SLG against AB-weighted league rates"},"caveats":["PARK-UNADJUSTED: no park-factor data exists in the corpus, so these are league-relative but not park-adjusted (true B-Ref ERA+/OPS+ also divide by a park factor)","OBP baseline uses a consistent (H+BB)/(AB+BB) reached-base rate for BOTH player and league — the source feed carries no HBP or SF, so this is not the full (H+BB+HBP)/(AB+BB+HBP+SF) OBP; SLG is exact from the hit-type columns","league resolved from team code + season (most-recently-founded franchise existing by that season); the same resolver builds the baseline and looks up the player, so ratios stay internally coherent","a (season, league) bucket below the sample floor (3000 AB batting / 1000 IP pitching) yields null — no noisy baselines","regular season only; postseason lines are excluded from league baselines and metrics","AL and NL and each historical/Negro league are normalized separately — never blended across leagues or eras"]}}],"dataSources":["MLB StatsAPI (statsapi.mlb.com — official public league API; facts only, raw payloads not republished)"],"generatedAt":"2026-07-03T03:21:00.501Z"}