[{"_id":"n383hopmfz69j7rdbh1ny56g","playerId":"402ddb96-0edf-4df7-9ba8-ffb201ef6a70","playedChartId":"3w2aaz0ryd58it6r3w0klu5r","score":966858},{"_id":"5e83ecd30102b60ea4a11fe9","playerId":"402ddb96-0edf-4df7-9ba8-ffb201ef6a70",/** the same player*/"playedChartId":"3w2aaz0ryd58it6r3w0klu5r","score":954201/** with lower score*/},{"_id":"629da76873dff6547eb1e9b3","playerId":"f6fe9c4d-98e6-450a-937c-d64848eacc40",/** the different player*/"playedChartId":"3w2aaz0ryd58it6r3w0klu5r",/** the same chart*/"score":902238}]

db.collection.aggregate([{$sort:{playerId:1,score:-1}},{$group:{_id:"$playerId",data:{$first:"$$ROOT"}}},{$replaceWith:"$data"},{$setWindowFields:{sortBy:{score:-1},output:{ranking:{$rank:{}}}}}])