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db.collection.aggregate([{"$set":{"results":{"$filter":{"input":"$results","cond":{"$eq":["$$this.gameref","Clubs"]}}}}},{"$unwind":"$results"},{"$sort":{"results.dateplayed":-1}},{"$group":{"_id":"$userref","results":{"$first":"$results"},"sessionref":{"$first":"$sessionref"}}}])