diff --git a/jetty-core/jetty-io/src/main/java/org/eclipse/jetty/io/Content.java b/jetty-core/jetty-io/src/main/java/org/eclipse/jetty/io/Content.java
index b46b6bca36a5..85f8b9627a2e 100644
--- a/jetty-core/jetty-io/src/main/java/org/eclipse/jetty/io/Content.java
+++ b/jetty-core/jetty-io/src/main/java/org/eclipse/jetty/io/Content.java
@@ -369,7 +369,7 @@ static ByteBuffer asByteBuffer(Source source) throws IOException
          * @param maxSize The maximum size to read, or -1 for no limit
          * @return A {@link CompletableFuture} that will be completed when the complete content is read or
          * failed if the max size is exceeded or there is a read error.
-         * @deprecated no replacement
+         * @deprecated use {@link #asByteArrayAsync(Source, int, Promise.Invocable)}
          */
         @Deprecated(forRemoval = true, since = "12.0.15")
         static CompletableFuture<byte[]> asByteArrayAsync(Source source, int maxSize)
@@ -383,6 +383,18 @@ static CompletableFuture<byte[]> asByteArrayAsync(Source source, int maxSize)
             });
         }
 
+        /**
+         * <p>Reads, non-blocking, the whole content source into a {@code byte} array.</p>
+         *
+         * @param source the source to read
+         * @param maxSize The maximum size to read, or -1 for no limit
+         * @param promise the {@link Promise.Invocable} to notify when the whole content has been read into a byte array.
+         */
+        static void asByteArrayAsync(Source source, int maxSize, Promise.Invocable<byte[]> promise)
+        {
+            asRetainableByteBuffer(source, null, false, maxSize, Promise.Invocable.toPromise(promise, RetainableByteBuffer::takeByteArray));
+        }
+
         /**
          * <p>Reads, non-blocking, the whole content source into a {@link ByteBuffer}.</p>
          *
diff --git a/jetty-core/jetty-io/src/test/java/org/eclipse/jetty/io/ContentSourceTest.java b/jetty-core/jetty-io/src/test/java/org/eclipse/jetty/io/ContentSourceTest.java
index 9b78c3fc4e02..a9ef220a5222 100644
--- a/jetty-core/jetty-io/src/test/java/org/eclipse/jetty/io/ContentSourceTest.java
+++ b/jetty-core/jetty-io/src/test/java/org/eclipse/jetty/io/ContentSourceTest.java
@@ -50,6 +50,7 @@
 import org.eclipse.jetty.util.FutureCallback;
 import org.eclipse.jetty.util.FuturePromise;
 import org.eclipse.jetty.util.IO;
+import org.eclipse.jetty.util.Promise;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assumptions;
 import org.junit.jupiter.api.BeforeEach;
@@ -1036,7 +1037,8 @@ public void testAsByteArrayAsync() throws Exception
     {
         TestContentSource source = new TestContentSource();
 
-        CompletableFuture<byte[]> completableFuture = Content.Source.asByteArrayAsync(source, -1);
+        CompletableFuture<byte[]> future = new CompletableFuture<>();
+        Content.Source.asByteArrayAsync(source, -1, Promise.Invocable.toPromise(future));
 
         Retainable.ReferenceCounter counter = new Retainable.ReferenceCounter();
         counter.retain();
@@ -1046,7 +1048,7 @@ public void testAsByteArrayAsync() throws Exception
         assertNotNull(todo);
         source.add(Content.Chunk.asChunk(BufferUtil.toBuffer("hello"), false, counter));
         todo.run();
-        assertFalse(completableFuture.isDone());
+        assertFalse(future.isDone());
 
         todo = source.takeDemand();
         assertNotNull(todo);
@@ -1056,9 +1058,9 @@ public void testAsByteArrayAsync() throws Exception
 
         todo = source.takeDemand();
         assertNull(todo);
-        assertTrue(completableFuture.isDone());
+        assertTrue(future.isDone());
 
-        byte[] buffer = completableFuture.get();
+        byte[] buffer = future.get();
         assertNotNull(buffer);
 
         assertThat(new String(buffer, UTF_8), equalTo("hello cruel world"));