diff --git a/src/engine/blocks.js b/src/engine/blocks.js
index 312c73779..0c90d1a64 100644
--- a/src/engine/blocks.js
+++ b/src/engine/blocks.js
@@ -407,7 +407,7 @@ class Blocks {
                 id="${block.id}"
                 type="${block.opcode}"
                 ${block.topLevel ?
-                    `x="${block.x} y="${block.y}` :
+                    `x="${block.x}" y="${block.y}"` :
                     ''
                 }
             >`;