diff --git a/src/models/player.ts b/src/models/player.ts
index f7c69bc..5dc87bd 100755
--- a/src/models/player.ts
+++ b/src/models/player.ts
@@ -6,7 +6,7 @@ import {
 } from "./stats";
 import {
     getMongoObjectCollection,
-    MongoStoredObject, MongoStoredObjectCollection,
+    MongoStoredObject, MongoStoredObjectCollection, StoredObject, StoredObjectCollection,
 } from "./utils";
 import {CellValue} from "../controllers/statsController";
 import mongo from "mongodb";
@@ -23,12 +23,12 @@ export interface StoredPlayerData {
     stats: PlayerStats;
 }
 
-interface StoredPlayerCollection {
-    findPlayerById(id: string): Promise<StoredPlayer>;
+interface StoredPlayerCollection extends StoredObjectCollection<StoredPlayer> {
+    findById(id: string): Promise<StoredPlayer>;
 }
 
 class MongoStoredPlayerCollection
-    extends MongoStoredObjectCollection<MongoStoredPlayer>
+    extends MongoStoredObjectCollection<MongoStoredPlayer, StoredPlayer>
     implements StoredPlayerCollection {
 
     private updater: PlayerStatsUpdater;
@@ -37,19 +37,19 @@ class MongoStoredPlayerCollection
         this.updater = new PlayerStatsUpdater();
     }
 
-    async findPlayerById(id: string): Promise<StoredPlayer> {
+    async findById(id: string): Promise<StoredPlayer> {
         const data = await this.findObjectById(id);
         return new MongoStoredPlayer(data);
     }
 }
 
-export interface StoredPlayer {
+export interface StoredPlayer extends StoredObject {
     nick(): string;
     setNick(newNick: string): Promise<void>;
     updateStats(results: PlayerGameResults & {outcome: OutcomeType}, ruleset: Ruleset): Promise<void>;
 }
 
-class MongoStoredPlayer extends MongoStoredObject implements StoredPlayer {
+class MongoStoredPlayer extends MongoStoredObject<StoredPlayerData> implements StoredPlayer {
     constructor(data: StoredPlayerData) {
         super(data);
     }
diff --git a/src/models/utils.ts b/src/models/utils.ts
index 0345bc0..3ce4363 100644
--- a/src/models/utils.ts
+++ b/src/models/utils.ts
@@ -18,7 +18,11 @@ export function getMongoObjectCollection(collectionName: string) {
     }
 }
 
-export abstract class MongoStoredObjectCollection<T extends MongoStoredObject<any>> {
+export interface StoredObjectCollection<K> {
+    findById(id: string): Promise<K>;
+}
+
+export abstract class MongoStoredObjectCollection<T extends MongoStoredObject<any>, K extends StoredObject> implements StoredObjectCollection<K> {
     protected mongoDbClientCollection: mongo.Collection;
     protected constructor(collectionClient: mongo.Collection) {
         this.mongoDbClientCollection = collectionClient;
@@ -28,6 +32,8 @@ export abstract class MongoStoredObjectCollection<T extends MongoStoredObject<an
         return this.mongoDbClientCollection!.findOne({_id: id});
     }
 
+    abstract async findById(id: string): Promise<K>;
+
     async save(...objects: T[]): Promise<void> {
         for (const object of objects) {
             await this.mongoDbClientCollection.findOneAndUpdate({_id: object.id()}, {...object.rawData()});
@@ -35,7 +41,12 @@ export abstract class MongoStoredObjectCollection<T extends MongoStoredObject<an
     }
 }
 
-export abstract class MongoStoredObject<T> {
+export interface StoredObject {
+    id(): string;
+    rawData(): any;
+}
+
+export abstract class MongoStoredObject<T> implements StoredObject {
     protected constructor(protected data: {_id: string} & T) {}
 
     id(): string {