{"sport":"mlb","slug":"mark-brown","bio":{"fullName":"Mark Brown","position":"P","team":"MIN","heightInches":74,"weightLbs":190,"birthDate":"1959-07-13","rookieSeason":1984,"lastSeason":1985,"status":"RET","externalIds":{"mlbam":"111573","chadwick":"c297f6b6","retro":"browm001","wikidata":"Q6766875"}},"draft":{"year":1980,"round":null,"pick":null,"team":null,"undrafted":false},"statTables":[{"id":"pitching","label":"Pitching","columns":[{"key":"g"},{"key":"gs"},{"key":"w"},{"key":"l"},{"key":"sv"},{"key":"ip"},{"key":"so"},{"key":"bb"},{"key":"h"},{"key":"er"},{"key":"hr"},{"key":"era"},{"key":"whip"}],"rows":[{"season":1984,"seasonType":"REG","team":"BAL","gamesPlayed":9,"values":{"g":9,"gs":0,"w":1,"l":2,"sv":0,"ip":23,"so":10,"bb":7,"h":22,"er":10,"hr":2,"era":3.91,"whip":1.26},"rowScope":"team"},{"season":1985,"seasonType":"REG","team":"MIN","gamesPlayed":6,"values":{"g":6,"gs":0,"w":0,"l":0,"sv":0,"ip":15.2,"so":5,"bb":7,"h":21,"er":12,"hr":1,"era":6.89,"whip":1.79},"rowScope":"team"}],"careerTotals":{"REG":{"g":15,"gs":0,"w":1,"l":2,"sv":0,"ip":38.2,"so":15,"bb":14,"h":43,"er":22,"hr":3,"era":5.12,"whip":1.47}}},{"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":1984,"seasonType":"REG","team":"BAL","values":{"ops_plus":null,"era_plus":99},"rowScope":"team"},{"season":1985,"seasonType":"REG","team":"MIN","values":{"ops_plus":null,"era_plus":58},"rowScope":"team"}],"careerTotals":{"REG":{"ops_plus":null,"era_plus":77}},"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":"2026-07-03T02:49:47.141Z"}