diff --git a/src/core/qgstaskmanager.cpp b/src/core/qgstaskmanager.cpp
index 7e1627676a9..9a3cb813dc3 100644
--- a/src/core/qgstaskmanager.cpp
+++ b/src/core/qgstaskmanager.cpp
@@ -57,8 +57,8 @@ qint64 QgsTask::elapsedTime() const
 
 void QgsTask::start()
 {
-  mNotStartedMutex.unlock();
   mNotFinishedMutex.lock();
+  mNotStartedMutex.unlock();
   mStartCount++;
   Q_ASSERT( mStartCount == 1 );