diff --git a/src/Player.php b/src/Player.php
index bab5452..84309a6 100644
--- a/src/Player.php
+++ b/src/Player.php
@@ -322,6 +322,43 @@ class Player
         return $total;
     }
 
+    /**
+     * Returns if player has played against all players of the array
+     *
+     * @param Player[] $players
+     * @return bool
+     */
+    public function hasPlayedAllPlayersOfArray(array $players): bool
+    {
+        $ownkey = array_search($this, $players);
+        if ($ownkey !== false) {
+            unset($players[$ownkey]);
+        }
+        $total = 0;
+        foreach ($players as $player) {
+            if (array_search($player, $this->Opponents) !== false) {
+                $total++;
+            }
+        }
+
+        return $total == count($players);
+    }
+
+    /**
+     * Returns all opponents of $this
+     *
+     * @return Player[]
+     */
+    private function opponents() {
+        $return = array();
+        foreach ($this->Pairings as $pairing) {
+            if (!empty($pairing->Opponent)) {
+                $return[] = $pairing->Opponent;
+            }
+        }
+        return $return;
+    }
+
     /**
      * Magic method to read out several fields. If field was not found it is being searched in the binary data fields
      *
@@ -334,6 +371,8 @@ class Player
             return $this->playedGames();
         } elseif ($key == 'NoOfWins') {
             return $this->noOfWins();
+        } elseif ($key == 'Opponents') {
+            return $this->opponents();
         } elseif (isset($this->BinaryData[$key])) {
             return $this->BinaryData[$key];
         }
diff --git a/src/Tournament.php b/src/Tournament.php
index ebacb50..5e3d76b 100644
--- a/src/Tournament.php
+++ b/src/Tournament.php
@@ -700,6 +700,15 @@ class Tournament
                 }
             }
         }
+        if($interestingplayers) {
+            $allintplayers = $interestingplayers;
+            $allintplayers[] = $player;
+            foreach($allintplayers as $player) {
+                if (!$player->hasPlayedAllPlayersOfArray($allintplayers)) {
+                    return 0;
+                }
+            }
+        }
         $points = 0;
         $totalmatches = 0;
         foreach ($player->Pairings as $pairing) {