diff --git a/src/platform/qt/GameController.cpp b/src/platform/qt/GameController.cpp
index d56a02ae2..2686bd235 100644
--- a/src/platform/qt/GameController.cpp
+++ b/src/platform/qt/GameController.cpp
@@ -68,7 +68,7 @@ void GameController::setDebugger(ARMDebugger* debugger) {
 		GBADetachDebugger(m_threadContext.gba);
 	}
 	m_threadContext.debugger = debugger;
-	if (m_threadContext.debugger) {
+	if (m_threadContext.debugger && GBAThreadHasStarted(&m_threadContext)) {
 		GBAAttachDebugger(m_threadContext.gba, m_threadContext.debugger);
 	}
 	setPaused(wasPaused);