diff --git a/src/formatting.rs b/src/formatting.rs
index 94ab400..f8821b7 100644
--- a/src/formatting.rs
+++ b/src/formatting.rs
@@ -24,18 +24,17 @@ impl DatadogLog {
         log.insert("timestamp".to_string(), self.timestamp.to_rfc3339().into());
         log.insert("level".to_string(), self.level.to_string().into());
 
-        let mut message = self.message;
-
         self.fields.sort();
 
-        for field in self.fields {
+        let mut message = self.message;
+
+        for field in &self.fields {
             // message is just a regular field
             if field.name != "message" {
-                message.push_str(&format!(
-                    " {}={}",
-                    field.name,
-                    field.value.trim_matches('\"')
-                ));
+                let value = field.value.trim_matches('\"');
+
+                message.push_str(&format!(" {}={}", field.name, value));
+                log.insert(format!("fields.{}", &field.name), value.into());
             }
         }
 
@@ -144,7 +143,7 @@ mod format {
             datadog_ids: None,
         };
 
-        assert_that(sut.format()).is(json!({"timestamp": "2022-01-01T00:00:00+00:00", "level": "INFO", "message": "Hello World! foo=bar", "target": "target"}).to_string());
+        assert_that(sut.format()).is(json!({"timestamp": "2022-01-01T00:00:00+00:00", "level": "INFO", "fields.foo": "bar", "message": "Hello World! foo=bar", "target": "target"}).to_string());
     }
 
     #[test]
@@ -173,7 +172,7 @@ mod format {
             datadog_ids: None,
         };
 
-        assert_that(sut.format()).is(json!({"timestamp": "2022-01-01T00:00:00+00:00", "level": "INFO", "message": "Hello World! a=c b=b c=a", "target": "target"}).to_string());
+        assert_that(sut.format()).is(json!({"timestamp": "2022-01-01T00:00:00+00:00", "level": "INFO", "fields.a": "c", "fields.b": "b", "fields.c": "a", "message": "Hello World! a=c b=b c=a", "target": "target"}).to_string());
     }
 
     #[macro_export]
diff --git a/src/layer.rs b/src/layer.rs
index 313592b..c4dfe30 100644
--- a/src/layer.rs
+++ b/src/layer.rs
@@ -110,7 +110,7 @@ mod simple_layer {
         let events = sink.events();
         assert_that(&events).size().is(1);
 
-        assert_that(events).first().contains("\",\"level\":\"INFO\",\"message\":\"Hello World! user=John Doe\",\"target\":\"datadog_formatting_layer::layer::simple_layer\"}");
+        assert_that(events).first().contains("\",\"level\":\"INFO\",\"fields.user\":\"John Doe\",\"message\":\"Hello World! user=John Doe\",\"target\":\"datadog_formatting_layer::layer::simple_layer\"}");
     }
 
     #[allow(clippy::redundant_clone)]
@@ -123,9 +123,9 @@ mod simple_layer {
         let events = sink.events();
         assert_that(&events).size().is(3);
 
-        assert_that(events.clone()).first().contains("\",\"level\":\"DEBUG\",\"message\":\"First Span! first_value=Argument\",\"target\":\"datadog_formatting_layer::layer::setup\"}");
-        assert_that(events.clone()).second().contains("\",\"level\":\"DEBUG\",\"message\":\"Second Span! attr=value first_value=Argument\",\"target\":\"datadog_formatting_layer::layer::setup\"}");
-        assert_that(events.clone()).third().contains("\",\"level\":\"INFO\",\"message\":\" attr=value first_value=Argument return=Return Value\",\"target\":\"datadog_formatting_layer::layer::setup\"}");
+        assert_that(events.clone()).first().contains("\",\"level\":\"DEBUG\",\"fields.first_value\":\"Argument\",\"message\":\"First Span! first_value=Argument\",\"target\":\"datadog_formatting_layer::layer::setup\"}");
+        assert_that(events.clone()).second().contains("\",\"level\":\"DEBUG\",\"fields.attr\":\"value\",\"fields.first_value\":\"Argument\",\"message\":\"Second Span! attr=value first_value=Argument\",\"target\":\"datadog_formatting_layer::layer::setup\"}");
+        assert_that(events.clone()).third().contains("\",\"level\":\"INFO\",\"fields.attr\":\"value\",\"fields.first_value\":\"Argument\",\"fields.return\":\"Return Value\",\"message\":\" attr=value first_value=Argument return=Return Value\",\"target\":\"datadog_formatting_layer::layer::setup\"}");
     }
 }