diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6ca3d363..a5604822 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 - [#1146](https://github.com/xmrig/xmrig/pull/1146) Fixed race condition in RandomX thread init.
 - [#1148](https://github.com/xmrig/xmrig/pull/1148) Fixed, on Linux linker marking entire executable as having an executable stack.
 - Fixed, for Argon2 algorithms command line options like `--threads` was ignored.
+- Fixed command line options for single pool, free order allowed again.
 
 # v3.1.0
 - [#1107](https://github.com/xmrig/xmrig/issues/1107#issuecomment-522235892) Added Argon2 algorithm family: `argon2/chukwa` and `argon2/wrkz`.
diff --git a/src/base/kernel/config/BaseTransform.cpp b/src/base/kernel/config/BaseTransform.cpp
index 8043c6e9..12e7d848 100644
--- a/src/base/kernel/config/BaseTransform.cpp
+++ b/src/base/kernel/config/BaseTransform.cpp
@@ -33,11 +33,12 @@
 #endif
 
 
-#include "base/kernel/config/BaseTransform.h"
-#include "base/kernel/Process.h"
-#include "base/io/log/Log.h"
-#include "base/kernel/interfaces/IConfig.h"
 #include "base/io/json/JsonChain.h"
+#include "base/io/log/Log.h"
+#include "base/kernel/config/BaseTransform.h"
+#include "base/kernel/interfaces/IConfig.h"
+#include "base/kernel/Process.h"
+#include "base/net/stratum/Pool.h"
 #include "core/config/Config_platform.h"
 
 
@@ -138,7 +139,19 @@ void xmrig::BaseTransform::transform(rapidjson::Document &doc, int key, const ch
         break;
 
     case IConfig::UrlKey: /* --url */
-        return add(doc, kPools, "url", arg, true);
+    {
+        if (!doc.HasMember(kPools)) {
+            doc.AddMember(rapidjson::StringRef(kPools), rapidjson::kArrayType, doc.GetAllocator());
+        }
+
+        rapidjson::Value &array = doc[kPools];
+        if (array.Size() == 0 || Pool(array[array.Size() - 1]).isValid()) {
+            array.PushBack(rapidjson::kObjectType, doc.GetAllocator());
+        }
+
+        set(doc, array[array.Size() - 1], "url", arg);
+        break;
+    }
 
     case IConfig::UserKey: /* --user */
         return add(doc, kPools, "user", arg);
diff --git a/src/base/net/stratum/Pool.cpp b/src/base/net/stratum/Pool.cpp
index 4d15ea47..ba31c35d 100644
--- a/src/base/net/stratum/Pool.cpp
+++ b/src/base/net/stratum/Pool.cpp
@@ -200,6 +200,9 @@ bool xmrig::Pool::isEqual(const Pool &other) const
 bool xmrig::Pool::parse(const char *url)
 {
     assert(url != nullptr);
+    if (url == nullptr) {
+        return false;
+    }
 
     const char *p    = strstr(url, "://");
     const char *base = url;