@@ -657,6 +657,11 @@ impl ExprSchemable for Expr {
     /// expression to the target [arrow::datatypes::DataType].
     fn cast_to(self, cast_to_type: &DataType, schema: &dyn ExprSchema) -> Result<Expr> {
         let this_type = self.get_type(schema)?;
+        // @HStack - see https://github.com/apache/datafusion/issues/19943
+        // currently we cannot activate this -  some failing tests
+        // at datafusion/datafusion/sqllogictest/test_files/case.slt:389
+        // datafusion/datafusion/sqllogictest/test_files/case.slt:400
+        // if this_type.equals_datatype(cast_to_type) {
         if this_type == *cast_to_type {
             return Ok(self);
         }
 
@@ -939,7 +939,14 @@ fn coerce_arguments_for_signature_with_scalar_udf(
     expressions
         .into_iter()
         .enumerate()
-        .map(|(i, expr)| expr.cast_to(&coerced_types[i], schema))
+        .map(|(i, expr)| {
+            let current_type = expr.get_type(schema)?;
+            // @HStack - deep projection fix
+            if func.name() == "array_element" && current_type.equals_datatype(&coerced_types[i]) {
+                return Ok(expr)
+            }
+            expr.cast_to(&coerced_types[i], schema)
+        })
         .collect()
 }