diff --git a/mysql-test/main/range_notembedded.result b/mysql-test/main/range_notembedded.result
index 9cd939031848e..9965969e1170d 100644
--- a/mysql-test/main/range_notembedded.result
+++ b/mysql-test/main/range_notembedded.result
@@ -124,7 +124,7 @@ left(@json, 2500)
             "sel_arg_weight_heuristic": 
             {
                 "key1_field": "kp1",
-                "key2_field": "kp2",
+                "key2_type": 3,
                 "key1_weight": 10,
                 "key2_weight": 10
             }
@@ -133,7 +133,7 @@ left(@json, 2500)
             "sel_arg_weight_heuristic": 
             {
                 "key1_field": "kp1",
-                "key2_field": "kp3",
+                "key2_type": 3,
                 "key1_weight": 10,
                 "key2_weight": 10
             }
@@ -142,7 +142,7 @@ left(@json, 2500)
             "sel_arg_weight_heuristic": 
             {
                 "key1_field": "kp1",
-                "key2_field": "kp4",
+                "key2_type": 3,
                 "key1_weight": 10,
                 "key2_weight": 10
             }
@@ -308,3 +308,75 @@ json_pretty(json_search(@trace, 'all', 'key1'))
     "$[0].analyzing_range_alternatives.range_scan_alternatives[0].index"
 ]
 drop table t1;
+#
+# MDEV-37510: Crash in sel_arg_and_weight_heuristic
+#
+SET @save_optimizer_trace=@@optimizer_trace;
+SET @save_optimizer_max_sel_arg_weight=@@optimizer_max_sel_arg_weight;
+SET optimizer_trace= 'enabled=on';
+SET optimizer_max_sel_arg_weight=1;
+CREATE TABLE t1 (c1 INT, c2 VARCHAR(10), c3 VARCHAR(10));
+CREATE TABLE t2 (c1 INT, c2 VARCHAR(10), c3 VARCHAR(10));
+INSERT INTO t1 values (2, 'two', 'prime'), (3, 'three', 'prime');
+INSERT INTO t2 values (2, 'two', '2_table'), (4, 'four', '2_table');
+EXPLAIN
+SELECT t1.c1, v1.c2 
+FROM 
+(
+t1
+JOIN 
+(
+SELECT c1, c2, c3 FROM t2
+UNION SELECT c1, c2, c3 FROM t2
+) v1
+ON (
+(t1.c1 = v1.c1 OR v1.c1 IS NULL) AND
+(t1.c2 = v1.c2 OR v1.c3 IS NULL) AND
+v1.c3 IN ('2_table', '3_table')
+)
+) 
+WHERE t1.c1 NOT IN (5, 6, 7);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+1	PRIMARY	<derived2>	ALL	distinct_key	NULL	NULL	NULL	4	Using where; Using join buffer (flat, BNL join)
+2	DERIVED	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
+3	UNION	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
+NULL	UNION RESULT	<union2,3>	ALL	NULL	NULL	NULL	NULL	NULL	
+set @trace= (select trace from information_schema.optimizer_trace);
+set @json= json_detailed(json_extract(@trace, '$**.setup_range_conditions'));
+select left(@json, 2500);
+left(@json, 2500)
+[
+    [
+        {
+            "sel_arg_weight_heuristic": 
+            {
+                "key1_type": 2,
+                "key2_type": 2,
+                "key1_weight": 1,
+                "key2_weight": 1
+            }
+        },
+        {
+            "sel_arg_weight_heuristic": 
+            {
+                "key1_type": 2,
+                "key2_type": 3,
+                "key1_weight": 1,
+                "key2_weight": 1
+            }
+        },
+        {
+            "enforce_sel_arg_weight_limit": 
+            {
+                "index": "distinct_key",
+                "old_weight": 2,
+                "new_weight": 0
+            }
+        }
+    ]
+]
+DROP TABLE t1, t2;
+SET optimizer_trace=@save_optimizer_trace;
+SET optimizer_max_sel_arg_weight=@save_optimizer_max_sel_arg_weight;
+# end of 11.4 tests
diff --git a/mysql-test/main/range_notembedded.test b/mysql-test/main/range_notembedded.test
index a13bb1d95c79a..47cad12139258 100644
--- a/mysql-test/main/range_notembedded.test
+++ b/mysql-test/main/range_notembedded.test
@@ -211,3 +211,45 @@ set @trace=json_extract((select trace from information_schema.optimizer_trace),
 select json_pretty(json_search(@trace, 'all', 'key1'));
 drop table t1;
 
+--echo #
+--echo # MDEV-37510: Crash in sel_arg_and_weight_heuristic
+--echo #
+SET @save_optimizer_trace=@@optimizer_trace;
+SET @save_optimizer_max_sel_arg_weight=@@optimizer_max_sel_arg_weight;
+
+SET optimizer_trace= 'enabled=on';
+SET optimizer_max_sel_arg_weight=1;
+
+CREATE TABLE t1 (c1 INT, c2 VARCHAR(10), c3 VARCHAR(10));
+CREATE TABLE t2 (c1 INT, c2 VARCHAR(10), c3 VARCHAR(10));
+
+INSERT INTO t1 values (2, 'two', 'prime'), (3, 'three', 'prime');
+INSERT INTO t2 values (2, 'two', '2_table'), (4, 'four', '2_table');
+
+EXPLAIN
+SELECT t1.c1, v1.c2 
+  FROM 
+  (
+    t1
+    JOIN 
+    (
+      SELECT c1, c2, c3 FROM t2
+      UNION SELECT c1, c2, c3 FROM t2
+    ) v1
+    ON (
+      (t1.c1 = v1.c1 OR v1.c1 IS NULL) AND
+      (t1.c2 = v1.c2 OR v1.c3 IS NULL) AND
+      v1.c3 IN ('2_table', '3_table')
+    )
+  ) 
+WHERE t1.c1 NOT IN (5, 6, 7);
+
+set @trace= (select trace from information_schema.optimizer_trace);
+set @json= json_detailed(json_extract(@trace, '$**.setup_range_conditions'));
+select left(@json, 2500);
+
+DROP TABLE t1, t2;
+
+SET optimizer_trace=@save_optimizer_trace;
+SET optimizer_max_sel_arg_weight=@save_optimizer_max_sel_arg_weight;
+--echo # end of 11.4 tests
diff --git a/sql/opt_range.cc b/sql/opt_range.cc
index ec3623c3e1fe2..b5108b4248587 100644
--- a/sql/opt_range.cc
+++ b/sql/opt_range.cc
@@ -11523,11 +11523,15 @@ bool sel_arg_and_weight_heuristic(RANGE_OPT_PARAM *param, SEL_ARG *key1,
     {
       Json_writer_object wrapper(param->thd);
       Json_writer_object obj(param->thd, "sel_arg_weight_heuristic");
-      obj.
-        add("key1_field", key1->field->field_name).
-        add("key2_field", key2->field->field_name).
-        add("key1_weight", (longlong)key1->weight).
-        add("key2_weight", (longlong)key2->weight);
+
+      if (key1->type == SEL_ARG::KEY_RANGE)
+        obj.add("key1_field", key1->field->field_name);
+      else
+        obj.add("key1_type", (uint) key1->type);
+
+      obj.add("key2_type", (uint) key2->type);
+      obj.add("key1_weight", (longlong) key1->weight);
+      obj.add("key2_weight", (longlong) key2->weight);
     }
     return true; // Discard key2
   }