diff --git a/CHANGES.txt b/CHANGES.txt
index b9ae253922..a301dc9baf 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,4 +1,5 @@
 5.1
+ * Fix error when trying to assign a tuple to target type not being a tuple (CASSANDRA-20237)
  * Fail CREATE TABLE LIKE statement if UDTs in target keyspace do not exist or they have different structure from ones in source keyspace (CASSANDRA-19966)
  * Support octet_length and length functions (CASSANDRA-20102)
  * Make JsonUtils serialize Instant always with the same format (CASSANDRA-20209)
diff --git a/src/java/org/apache/cassandra/cql3/terms/Tuples.java b/src/java/org/apache/cassandra/cql3/terms/Tuples.java
index 6825a16b98..f9ba523567 100644
--- a/src/java/org/apache/cassandra/cql3/terms/Tuples.java
+++ b/src/java/org/apache/cassandra/cql3/terms/Tuples.java
@@ -68,14 +68,14 @@ public final class Tuples
             if (elements.size() == 1 && !checkIfTupleType(receiver.type))
                 return elements.get(0).prepare(keyspace, receiver);
 
+            validateTupleAssignableTo(receiver, elements);
+
             TupleType tupleType = getTupleType(receiver.type);
 
             if (elements.size() != tupleType.size())
                 throw invalidRequest("Expected %d elements in value for tuple %s, but got %d: %s",
                                      tupleType.size(), receiver.name, elements.size(), this);
 
-            validateTupleAssignableTo(receiver, elements);
-
             List<Term> values = new ArrayList<>(elements.size());
             boolean allTerminal = true;
             for (int i = 0; i < elements.size(); i++)
diff --git a/test/unit/org/apache/cassandra/cql3/validation/entities/TupleTypeTest.java b/test/unit/org/apache/cassandra/cql3/validation/entities/TupleTypeTest.java
index 452bb0bc36..90c9778df4 100644
--- a/test/unit/org/apache/cassandra/cql3/validation/entities/TupleTypeTest.java
+++ b/test/unit/org/apache/cassandra/cql3/validation/entities/TupleTypeTest.java
@@ -149,7 +149,7 @@ public class TupleTypeTest extends CQLTester
 
         assertInvalidSyntax("INSERT INTO %s (k, t) VALUES (0, ())");
 
-        assertInvalidMessage("Expected 3 elements in value for tuple t, but got 4: (2, 'foo', 3.1, 'bar')",
+        assertInvalidMessage("Invalid tuple literal for t: too many elements. Type frozen<tuple<int, text, double>> expects 3 but got 4",
                              "INSERT INTO %s (k, t) VALUES (0, (2, 'foo', 3.1, 'bar'))");
 
         createTable("CREATE TABLE %s (k int PRIMARY KEY, t frozen<tuple<int, tuple<int, text, double>>>)");
@@ -159,6 +159,9 @@ public class TupleTypeTest extends CQLTester
 
         assertInvalidMessage("Invalid tuple literal for t: component 1 is not of type frozen<tuple<int, text, double>>",
                              "INSERT INTO %s (k, t) VALUES (0, (1, (1, '1', 1.0, 1)))");
+
+        assertInvalidMessage("Invalid tuple type literal for k of type int",
+                             "SELECT * FROM %s WHERE k = ('a', 'b')");
     }
 
     @Test
diff --git a/test/unit/org/apache/cassandra/cql3/validation/operations/SelectMultiColumnRelationTest.java b/test/unit/org/apache/cassandra/cql3/validation/operations/SelectMultiColumnRelationTest.java
index 1029196754..2fe3cffa7f 100644
--- a/test/unit/org/apache/cassandra/cql3/validation/operations/SelectMultiColumnRelationTest.java
+++ b/test/unit/org/apache/cassandra/cql3/validation/operations/SelectMultiColumnRelationTest.java
@@ -58,7 +58,7 @@ public class SelectMultiColumnRelationTest extends CQLTester
         createTable("CREATE TABLE %s (a int, b int, c int, d int, PRIMARY KEY (a, b, c, d))");
 
         assertInvalidSyntax("SELECT * FROM %s WHERE a = 0 AND (b, c) > ()");
-        assertInvalidMessage("Expected 2 elements in value for tuple (b, c), but got 3: (?, ?, ?)",
+        assertInvalidMessage("Invalid tuple literal for (b, c): too many elements. Type frozen<tuple<int, int>> expects 2 but got 3",
                              "SELECT * FROM %s WHERE a = 0 AND (b, c) > (?, ?, ?)", 1, 2, 3);
         assertInvalidMessage("Invalid null value for c in tuple (b, c)",
                              "SELECT * FROM %s WHERE a = 0 AND (b, c) > (?, ?)", 1, null);
@@ -72,7 +72,7 @@ public class SelectMultiColumnRelationTest extends CQLTester
         // Wrong number of values
         assertInvalidMessage("Expected 3 elements in value for tuple (b, c, d), but got 2: (?, ?)",
                              "SELECT * FROM %s WHERE a=0 AND (b, c, d) IN ((?, ?))", 0, 1);
-        assertInvalidMessage("Expected 3 elements in value for tuple (b, c, d), but got 5: (?, ?, ?, ?, ?)",
+        assertInvalidMessage("Invalid tuple literal for (b, c, d): too many elements. Type frozen<tuple<int, int, int>> expects 3 but got 5",
                              "SELECT * FROM %s WHERE a=0 AND (b, c, d) IN ((?, ?, ?, ?, ?))", 0, 1, 2, 3, 4);
 
         // Missing first clustering column