diff --git a/dd-java-agent/instrumentation/java-lang/src/main/java/datadog/trace/instrumentation/java/lang/StringBuilderCallSite.java b/dd-java-agent/instrumentation/java-lang/src/main/java/datadog/trace/instrumentation/java/lang/StringBuilderCallSite.java
index 635d7700d30..b56d4f50424 100644
--- a/dd-java-agent/instrumentation/java-lang/src/main/java/datadog/trace/instrumentation/java/lang/StringBuilderCallSite.java
+++ b/dd-java-agent/instrumentation/java-lang/src/main/java/datadog/trace/instrumentation/java/lang/StringBuilderCallSite.java
@@ -162,6 +162,7 @@ public static String afterSubstring(
   }
 
   @CallSite.After("java.lang.CharSequence java.lang.StringBuilder.subSequence(int, int)")
+  @CallSite.After("java.lang.CharSequence java.lang.StringBuffer.subSequence(int, int)")
   public static CharSequence afterSubSequence(
       @CallSite.This final CharSequence self,
       @CallSite.Argument final int beginIndex,
diff --git a/dd-java-agent/instrumentation/java-lang/src/test/groovy/datadog/trace/instrumentation/java/lang/StringBuilderCallSiteTest.groovy b/dd-java-agent/instrumentation/java-lang/src/test/groovy/datadog/trace/instrumentation/java/lang/StringBuilderCallSiteTest.groovy
index b5f73c04112..c989aa9f77d 100644
--- a/dd-java-agent/instrumentation/java-lang/src/test/groovy/datadog/trace/instrumentation/java/lang/StringBuilderCallSiteTest.groovy
+++ b/dd-java-agent/instrumentation/java-lang/src/test/groovy/datadog/trace/instrumentation/java/lang/StringBuilderCallSiteTest.groovy
@@ -246,6 +246,7 @@ class StringBuilderCallSiteTest extends AgentTestRunner {
     where:
     type      | suite                        | param         | beginIndex | endIndex | expected
     "builder" | new TestStringBuilderSuite() | sb('012345')  | 1          | 5        | '1234'
+    "buffer"  | new TestStringBufferSuite()  | sbf('012345') | 1          | 5        | '1234'
   }
 
   private static class BrokenToString {