diff --git a/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkAsyncHttpClient.java b/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkAsyncHttpClient.java
index 7b869646711db..bc91fe9a0cedb 100644
--- a/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkAsyncHttpClient.java
+++ b/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkAsyncHttpClient.java
@@ -96,8 +96,7 @@ private Mono<java.net.http.HttpRequest> toJdkHttpRequest(HttpRequest request) {
                 for (HttpHeader header : headers) {
                     final String headerName = header.getName();
                     if (!restrictedHeaders.contains(headerName)) {
-                        final String headerValue = header.getValue();
-                        builder.setHeader(headerName, headerValue);
+                        header.getValuesList().forEach(headerValue -> builder.header(headerName, headerValue));
                     } else {
                         logger.warning("The header '" + headerName + "' is restricted by default in JDK HttpClient 12 "
                             + "and above. This header can be added to allow list in JAVA_HOME/conf/net.properties "
@@ -135,7 +134,7 @@ private static BodyPublisher toBodyPublisher(Flux<ByteBuffer> bbPublisher, Strin
         } else {
             long contentLengthLong = Long.parseLong(contentLength);
             if (contentLengthLong < 1) {
-                return fromPublisher(bbFlowPublisher);
+                return noBody();
             } else {
                 return fromPublisher(bbFlowPublisher, contentLengthLong);
             }
diff --git a/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkHttpResponse.java b/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkHttpResponse.java
index 76d4a091d922e..290c04c2398cb 100644
--- a/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkHttpResponse.java
+++ b/sdk/core/azure-core-http-jdk-httpclient/src/main/java/com/azure/core/http/jdk/httpclient/JdkHttpResponse.java
@@ -33,7 +33,11 @@ public Flux<ByteBuffer> getBody() {
 
     @Override
     public Mono<byte[]> getBodyAsByteArray() {
-        return FluxUtil.collectBytesFromNetworkResponse(getBody(), getHeaders());
+        return FluxUtil.collectBytesFromNetworkResponse(getBody(), getHeaders())
+            // Map empty byte[] into Mono.empty, this matches how the other HttpResponse implementations handle this.
+            .flatMap(bytes -> (bytes == null || bytes.length == 0)
+                ? Mono.empty()
+                : Mono.just(bytes));
     }
 
     @Override