diff --git a/UI/GameScreen.cpp b/UI/GameScreen.cpp
index 66f071efb0..86c01d86c8 100644
--- a/UI/GameScreen.cpp
+++ b/UI/GameScreen.cpp
@@ -51,6 +51,7 @@
 #include "UI/GameScreen.h"
 #include "UI/GameSettingsScreen.h"
 #include "UI/GameInfoCache.h"
+#include "UI/InstallUpdateScreen.h"
 #include "UI/BaseScreens.h"
 #include "UI/MiscScreens.h"
 #include "UI/MainScreen.h"
@@ -658,6 +659,17 @@ void GameScreen::CreateContextMenu(UI::ViewGroup *parent) {
 		btnDeleteUpdate->OnClick.Handle(this, &GameScreen::OnDeleteGameUpdate);
 	}
 
+	// Most discs carry a firmware updater, and the firmware inside it is what our flash0 wants.
+	// Not while a game is running, though - installing wipes the NAND the running game has mounted.
+	if (!inGame_ && (knownFlags_ & GameInfoFlags::BUNDLED_UPDATE_INFO) && info_->bundledUpdate.present) {
+		auto iz = GetI18NCategory(I18NCat::INSTALLZIP);
+		Choice *btnInstallFirmware = parent->Add(new Choice(iz->T("Install PSP firmware update"), ImageID("I_FOLDER_UPLOAD")));
+		const BundledUpdateInfo update = info_->bundledUpdate;
+		btnInstallFirmware->OnClick.Add([this, update](UI::EventParams &e) {
+			screenManager()->push(new InstallUpdateScreen(gamePath_, update.title, false, update.archiveSize));
+		});
+	}
+
 	// Don't want to be able to delete the game while it's running.
 	if (!inGame_) {
 		Choice *deleteChoice = parent->Add(new Choice(ga->T("Delete Game"), ImageID("I_WARNING")));
diff --git a/UI/InstallUpdateScreen.cpp b/UI/InstallUpdateScreen.cpp
index 6a0e98e453..8cb94d2458 100644
--- a/UI/InstallUpdateScreen.cpp
+++ b/UI/InstallUpdateScreen.cpp
@@ -36,12 +36,13 @@
 #include "UI/MiscViews.h"
 #include "UI/EmuScreen.h"
 
-InstallUpdateScreen::InstallUpdateScreen(const Path &path, std::string_view title, bool allowRun)
+InstallUpdateScreen::InstallUpdateScreen(const Path &path, std::string_view title, bool allowRun, u64 archiveSize)
 	: UISimpleBaseDialogScreen(Path(), SimpleDialogFlags::ContentsCanScroll), path_(path), title_(title), allowRun_(allowRun) {
 	destination_ = GetSysDirectory(DIRECTORY_NAND);
 
+	fileSize_ = archiveSize;
 	File::FileInfo fileInfo;
-	if (File::GetFileInfo(path_, &fileInfo)) {
+	if (fileSize_ == 0 && File::GetFileInfo(path_, &fileInfo)) {
 		fileSize_ = fileInfo.size;
 	}
 	// There's no practical way to merge two firmwares, so an install replaces whatever is there.
diff --git a/UI/InstallUpdateScreen.h b/UI/InstallUpdateScreen.h
index 7c7933fc6e..69b7eb1da1 100644
--- a/UI/InstallUpdateScreen.h
+++ b/UI/InstallUpdateScreen.h
@@ -33,15 +33,19 @@
 #include "UI/BaseScreens.h"
 #include "UI/SimpleDialogScreen.h"
 
-// An official PSP firmware updater (a PSP/GAME/UPDATE/EBOOT.PBP, or the folder holding one).
-// Running it isn't going to get anyone anywhere, but the firmware inside it is exactly what the
-// emulated flash0/flash1 want, so offer to unpack it into the NAND directory instead.
+// An official PSP firmware updater: a PSP/GAME/UPDATE/EBOOT.PBP (or the folder holding one), or
+// a game disc, most of which carry one at PSP_GAME/SYSDIR/UPDATE/DATA.BIN. Running an updater
+// isn't going to get anyone anywhere, but the firmware inside it is exactly what the emulated
+// flash0/flash1 want, so offer to unpack it into the NAND directory instead.
 class InstallUpdateScreen : public UISimpleBaseDialogScreen {
 public:
 	// title is the updater's SFO title, which already carries the version ("PSP Update ver 6.61").
 	// allowRun offers to boot the updater instead of unpacking it - which makes sense when the
 	// user picked the updater to launch it, but not when they came here to install a firmware.
-	InstallUpdateScreen(const Path &path, std::string_view title, bool allowRun);
+	// archiveSize is how big the firmware itself is; pass it for a disc, where the size of the
+	// file we were handed is the game's and says nothing about what's being installed. Zero means
+	// "the file is the updater", which is the PBP case.
+	InstallUpdateScreen(const Path &path, std::string_view title, bool allowRun, u64 archiveSize = 0);
 
 	void CreateDialogViews(UI::ViewGroup *parent) override;
 	void update() override;