diff --git a/src/tuple.cr b/src/tuple.cr
index 3c9efe414421..2f9cde352e4f 100644
--- a/src/tuple.cr
+++ b/src/tuple.cr
@@ -545,7 +545,11 @@ struct Tuple
   # {1, 2, 3, 4, 5}.to_a # => [1, 2, 3, 4, 5]
   # ```
   def to_a : Array(Union(*T))
-    to_a(&.itself)
+    {% if compare_versions(Crystal::VERSION, "1.1.0") < 0 %}
+      to_a(&.itself.as(Union(*T)))
+    {% else %}
+      to_a(&.itself)
+    {% end %}
   end
 
   # Returns an `Array` with the results of running *block* against each element of the tuple.