diff --git a/src/OpenTelemetry.Exporter.OneCollector/CHANGELOG.md b/src/OpenTelemetry.Exporter.OneCollector/CHANGELOG.md
index a1852a68e2..cad40dcf22 100644
--- a/src/OpenTelemetry.Exporter.OneCollector/CHANGELOG.md
+++ b/src/OpenTelemetry.Exporter.OneCollector/CHANGELOG.md
@@ -6,6 +6,15 @@
   `RegisterPayloadTransmittedCallback` API.
   ([#1309](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/1309))
 
+* Added support for sending `LogRecord.Body` as common schema `body` if
+  `{OriginalFormat}` key is not found.
+  ([#1321](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/1321))
+
+* Added support for sending `LogRecord.FormattedMessage` (if set) as common
+  schema `formattedMessage` if it differs from the detected template (either
+  `{OriginalFormat}` key or `LogRecord.Body`).
+  ([#1321](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/1321))
+
 ## 1.5.1
 
 Released 2023-Aug-07
diff --git a/src/OpenTelemetry.Exporter.OneCollector/Internal/Serialization/LogRecordCommonSchemaJsonSerializer.cs b/src/OpenTelemetry.Exporter.OneCollector/Internal/Serialization/LogRecordCommonSchemaJsonSerializer.cs
index 9ca6abf692..7c4f80351d 100644
--- a/src/OpenTelemetry.Exporter.OneCollector/Internal/Serialization/LogRecordCommonSchemaJsonSerializer.cs
+++ b/src/OpenTelemetry.Exporter.OneCollector/Internal/Serialization/LogRecordCommonSchemaJsonSerializer.cs
@@ -28,6 +28,7 @@ internal sealed class LogRecordCommonSchemaJsonSerializer : CommonSchemaJsonSeri
     private static readonly JsonEncodedText SeverityTextProperty = JsonEncodedText.Encode("severityText");
     private static readonly JsonEncodedText SeverityNumberProperty = JsonEncodedText.Encode("severityNumber");
     private static readonly JsonEncodedText BodyProperty = JsonEncodedText.Encode("body");
+    private static readonly JsonEncodedText FormattedMessageProperty = JsonEncodedText.Encode("formattedMessage");
     private static readonly JsonEncodedText DistributedTraceExtensionProperty = JsonEncodedText.Encode("dt");
     private static readonly JsonEncodedText DistributedTraceExtensionTraceIdProperty = JsonEncodedText.Encode("traceId");
     private static readonly JsonEncodedText DistributedTraceExtensionSpanIdProperty = JsonEncodedText.Encode("spanId");
@@ -131,7 +132,7 @@ protected override void SerializeItemToJson(Resource resource, LogRecord item, C
         writer.WriteString(SeverityTextProperty, LogLevelToSeverityTextMappings[logLevel]);
         writer.WriteNumber(SeverityNumberProperty, LogLevelToSeverityNumberMappings[logLevel]);
 
-        string? body = null;
+        string? originalFormat = null;
 
         if (item.Attributes != null)
         {
@@ -146,7 +147,7 @@ protected override void SerializeItemToJson(Resource resource, LogRecord item, C
 
                 if (attribute.Key == "{OriginalFormat}")
                 {
-                    body = attribute.Value as string;
+                    originalFormat = attribute.Value as string;
                     continue;
                 }
 
@@ -160,13 +161,29 @@ protected override void SerializeItemToJson(Resource resource, LogRecord item, C
             }
         }
 
-        if (!string.IsNullOrEmpty(body))
+        var hasBody = false;
+
+        if (!string.IsNullOrEmpty(originalFormat))
+        {
+            writer.WriteString(BodyProperty, originalFormat);
+            hasBody = true;
+        }
+        else if (!string.IsNullOrEmpty(item.Body))
         {
-            writer.WriteString(BodyProperty, body);
+            writer.WriteString(BodyProperty, item.Body);
+            hasBody = true;
         }
         else if (!string.IsNullOrEmpty(item.FormattedMessage))
         {
             writer.WriteString(BodyProperty, item.FormattedMessage);
+            writer.WriteString(FormattedMessageProperty, item.FormattedMessage);
+        }
+
+        if (hasBody
+            && !string.IsNullOrEmpty(item.FormattedMessage)
+            && item.Body != item.FormattedMessage)
+        {
+            writer.WriteString(FormattedMessageProperty, item.FormattedMessage);
         }
 
         SerializeResourceToJsonInsideCurrentObject(resource, serializationState);
@@ -184,8 +201,9 @@ private void SerializeExtensionPropertiesToJson(LogRecord item, Utf8JsonWriter w
     {
         var hasTraceContext = item.TraceId != default;
         var hasException = item.Exception != null;
+        var hasExtensions = serializationState.ExtensionAttributeCount > 0;
 
-        if (!hasTraceContext && !hasException && serializationState.ExtensionAttributeCount <= 0)
+        if (!hasTraceContext && !hasException && !hasExtensions)
         {
             return;
         }
@@ -215,7 +233,10 @@ private void SerializeExtensionPropertiesToJson(LogRecord item, Utf8JsonWriter w
             writer.WriteEndObject();
         }
 
-        serializationState.SerializeExtensionPropertiesToJson(writeExtensionObjectEnvelope: false);
+        if (hasExtensions)
+        {
+            serializationState.SerializeExtensionPropertiesToJson(writeExtensionObjectEnvelope: false);
+        }
 
         writer.WriteEndObject();
     }
diff --git a/test/OpenTelemetry.Exporter.OneCollector.Tests/LogRecordCommonSchemaJsonSerializerTests.cs b/test/OpenTelemetry.Exporter.OneCollector.Tests/LogRecordCommonSchemaJsonSerializerTests.cs
index 80a1894ada..cabe61439a 100644
--- a/test/OpenTelemetry.Exporter.OneCollector.Tests/LogRecordCommonSchemaJsonSerializerTests.cs
+++ b/test/OpenTelemetry.Exporter.OneCollector.Tests/LogRecordCommonSchemaJsonSerializerTests.cs
@@ -119,7 +119,21 @@ public void LogRecordOriginalFormatBodyJsonTest()
         });
 
         Assert.Equal(
-            $"{{\"ver\":\"4.0\",\"name\":\"Namespace.Name\",\"time\":\"2032-01-18T10:11:12Z\",\"iKey\":\"o:tenant-token\",\"data\":{{\"severityText\":\"Trace\",\"severityNumber\":1,\"body\":\"hello world\"}}}}\n",
+            $"{{\"ver\":\"4.0\",\"name\":\"Namespace.Name\",\"time\":\"2032-01-18T10:11:12Z\",\"iKey\":\"o:tenant-token\",\"data\":{{\"severityText\":\"Trace\",\"severityNumber\":1,\"body\":\"hello world\",\"formattedMessage\":\"goodbye world\"}}}}\n",
+            json);
+    }
+
+    [Fact]
+    public void LogRecordBodyJsonTest()
+    {
+        string json = GetLogRecordJson(1, (index, logRecord) =>
+        {
+            logRecord.Body = "hello world";
+            logRecord.FormattedMessage = "goodbye world";
+        });
+
+        Assert.Equal(
+            $"{{\"ver\":\"4.0\",\"name\":\"Namespace.Name\",\"time\":\"2032-01-18T10:11:12Z\",\"iKey\":\"o:tenant-token\",\"data\":{{\"severityText\":\"Trace\",\"severityNumber\":1,\"body\":\"hello world\",\"formattedMessage\":\"goodbye world\"}}}}\n",
             json);
     }
 
@@ -132,7 +146,7 @@ public void LogRecordFormattedMessageBodyJsonTest()
         });
 
         Assert.Equal(
-            $"{{\"ver\":\"4.0\",\"name\":\"Namespace.Name\",\"time\":\"2032-01-18T10:11:12Z\",\"iKey\":\"o:tenant-token\",\"data\":{{\"severityText\":\"Trace\",\"severityNumber\":1,\"body\":\"goodbye world\"}}}}\n",
+            $"{{\"ver\":\"4.0\",\"name\":\"Namespace.Name\",\"time\":\"2032-01-18T10:11:12Z\",\"iKey\":\"o:tenant-token\",\"data\":{{\"severityText\":\"Trace\",\"severityNumber\":1,\"body\":\"goodbye world\",\"formattedMessage\":\"goodbye world\"}}}}\n",
             json);
     }