diff --git a/src/arenas/Battleship/act.php b/src/arenas/Battleship/act.php
index d948505..091e900 100644
--- a/src/arenas/Battleship/act.php
+++ b/src/arenas/Battleship/act.php
@@ -99,8 +99,8 @@ switch ($_POST['act']){
 	  }
 	  
 	  //init grid
-	  for($y = 0; $y < $height; $y++){
-	    for($x = 0; $x < $width; $x++){
+	  for($y = 0; $y < $postValues['gridHeight']; $y++){
+	    for($x = 0; $x < $postValues['gridWidth']; $x++){
 		    $grid[$player][$y][$x]=0;
 	    }
 	  }
diff --git a/src/arenas/Battleship/functions.php b/src/arenas/Battleship/functions.php
index 7f1e08e..deca0ce 100644
--- a/src/arenas/Battleship/functions.php
+++ b/src/arenas/Battleship/functions.php
@@ -54,9 +54,12 @@ function get_IA_Response($iaUrl,$postParams){
     return htmlentities($output);
 }
 function place_ship_on_map($x1,$y1,$x2,$y2,$map){
-  if (($x1 <> $x2) && ($y1 <> $y2)){
-    return false;
+  if ((($x1 <> $x2) && ($y1 <> $y2))
+    OR (!isset($map[$y1][$x1]))
+    OR (!isset($map[$y2][$x2]))){
+      return false;
   }
+  
 
   if($x1 == $x2){
     //horizontal ship