diff --git a/rpcs3/Emu/RSX/GL/GLDraw.cpp b/rpcs3/Emu/RSX/GL/GLDraw.cpp
index 0da7ddc068..1226976bf4 100644
--- a/rpcs3/Emu/RSX/GL/GLDraw.cpp
+++ b/rpcs3/Emu/RSX/GL/GLDraw.cpp
@@ -144,10 +144,16 @@ void GLGSRender::update_draw_state()
 		bool color_mask_r = rsx::method_registers.color_mask_r(index);
 		bool color_mask_a = rsx::method_registers.color_mask_a(index);
 
-		if (rsx::method_registers.surface_color() == rsx::surface_color_format::g8b8)
+		switch (rsx::method_registers.surface_color())
 		{
-			//Map GB components onto RG
+		case rsx::surface_color_format::b8:
+			rsx::get_b8_colormask(color_mask_r, color_mask_g, color_mask_b, color_mask_a);
+			break;
+		case rsx::surface_color_format::g8b8:
 			rsx::get_g8b8_r8g8_colormask(color_mask_r, color_mask_g, color_mask_b, color_mask_a);
+			break;
+		default:
+			break;
 		}
 
 		gl_state.color_maski(index, color_mask_r, color_mask_g, color_mask_b, color_mask_a);
diff --git a/rpcs3/Emu/RSX/GL/GLGSRender.cpp b/rpcs3/Emu/RSX/GL/GLGSRender.cpp
index 4ac300af65..691ed21721 100644
--- a/rpcs3/Emu/RSX/GL/GLGSRender.cpp
+++ b/rpcs3/Emu/RSX/GL/GLGSRender.cpp
@@ -613,10 +613,16 @@ void GLGSRender::clear_surface(u32 arg)
 			colormask = 0;
 			break;
 		}
+		case rsx::surface_color_format::b8:
+		{
+			rsx::get_b8_clear_color(clear_r, clear_g, clear_b, clear_a);
+			colormask = rsx::get_b8_clearmask(colormask);
+			break;
+		}
 		case rsx::surface_color_format::g8b8:
 		{
 			rsx::get_g8b8_clear_color(clear_r, clear_g, clear_b, clear_a);
-			colormask = rsx::get_g8b8_r8g8_colormask(colormask);
+			colormask = rsx::get_g8b8_r8g8_clearmask(colormask);
 			break;
 		}
 		case rsx::surface_color_format::a8b8g8r8:
@@ -624,7 +630,7 @@ void GLGSRender::clear_surface(u32 arg)
 		case rsx::surface_color_format::x8b8g8r8_z8b8g8r8:
 		{
 			rsx::get_abgr8_clear_color(clear_r, clear_g, clear_b, clear_a);
-			colormask = rsx::get_abgr8_colormask(colormask);
+			colormask = rsx::get_abgr8_clearmask(colormask);
 			break;
 		}
 		default:
diff --git a/rpcs3/Emu/RSX/VK/VKGSRender.cpp b/rpcs3/Emu/RSX/VK/VKGSRender.cpp
index f9c18e0d7b..24d9eada0f 100644
--- a/rpcs3/Emu/RSX/VK/VKGSRender.cpp
+++ b/rpcs3/Emu/RSX/VK/VKGSRender.cpp
@@ -1308,10 +1308,17 @@ void VKGSRender::clear_surface(u32 mask)
 				colormask = 0;
 				break;
 			}
+			case rsx::surface_color_format::b8:
+			{
+				rsx::get_b8_clear_color(clear_r, clear_g, clear_b, clear_a);
+				colormask = rsx::get_b8_clearmask(colormask);
+				use_fast_clear = (colormask == RSX_GCM_CLEAR_RED_BIT);
+				break;
+			}
 			case rsx::surface_color_format::g8b8:
 			{
 				rsx::get_g8b8_clear_color(clear_r, clear_g, clear_b, clear_a);
-				colormask = rsx::get_g8b8_r8g8_colormask(colormask);
+				colormask = rsx::get_g8b8_r8g8_clearmask(colormask);
 				use_fast_clear = (colormask == (RSX_GCM_CLEAR_RED_BIT | RSX_GCM_CLEAR_GREEN_BIT));
 				break;
 			}
@@ -1320,7 +1327,7 @@ void VKGSRender::clear_surface(u32 mask)
 			case rsx::surface_color_format::x8b8g8r8_z8b8g8r8:
 			{
 				rsx::get_abgr8_clear_color(clear_r, clear_g, clear_b, clear_a);
-				colormask = rsx::get_abgr8_colormask(colormask);
+				colormask = rsx::get_abgr8_clearmask(colormask);
 				[[fallthrough]];
 			}
 			default:
@@ -1646,8 +1653,17 @@ bool VKGSRender::load_program()
 		bool color_mask_r = rsx::method_registers.color_mask_r(index);
 		bool color_mask_a = rsx::method_registers.color_mask_a(index);
 
-		if (rsx::method_registers.surface_color() == rsx::surface_color_format::g8b8)
+		switch (rsx::method_registers.surface_color())
+		{
+		case rsx::surface_color_format::b8:
+			rsx::get_b8_colormask(color_mask_r, color_mask_g, color_mask_b, color_mask_a);
+			break;
+		case rsx::surface_color_format::g8b8:
 			rsx::get_g8b8_r8g8_colormask(color_mask_r, color_mask_g, color_mask_b, color_mask_a);
+			break;
+		default:
+			break;
+		}
 
 		properties.state.set_color_mask(index, color_mask_r, color_mask_g, color_mask_b, color_mask_a);
 	}
diff --git a/rpcs3/Emu/RSX/rsx_utils.h b/rpcs3/Emu/RSX/rsx_utils.h
index 36cdb8476c..34d68df413 100644
--- a/rpcs3/Emu/RSX/rsx_utils.h
+++ b/rpcs3/Emu/RSX/rsx_utils.h
@@ -726,11 +726,11 @@ namespace rsx
 	}
 
 	// Convert color write mask for G8B8 to R8G8
-	static inline u32 get_g8b8_r8g8_colormask(u32 mask)
+	static inline u32 get_g8b8_r8g8_clearmask(u32 mask)
 	{
 		u32 result = 0;
-		if (mask & 0x20) result |= 0x20;
-		if (mask & 0x40) result |= 0x10;
+		if (mask & RSX_GCM_CLEAR_GREEN_BIT) result |= RSX_GCM_CLEAR_GREEN_BIT;
+		if (mask & RSX_GCM_CLEAR_BLUE_BIT) result |= RSX_GCM_CLEAR_RED_BIT;
 
 		return result;
 	}
@@ -747,13 +747,13 @@ namespace rsx
 		red = blue;
 	}
 
-	static inline u32 get_abgr8_colormask(u32 mask)
+	static inline u32 get_abgr8_clearmask(u32 mask)
 	{
 		u32 result = 0;
-		if (mask & 0x10) result |= 0x40;
-		if (mask & 0x20) result |= 0x20;
-		if (mask & 0x40) result |= 0x10;
-		if (mask & 0x80) result |= 0x80;
+		if (mask & RSX_GCM_CLEAR_RED_BIT) result |= RSX_GCM_CLEAR_BLUE_BIT;
+		if (mask & RSX_GCM_CLEAR_GREEN_BIT) result |= RSX_GCM_CLEAR_GREEN_BIT;
+		if (mask & RSX_GCM_CLEAR_BLUE_BIT) result |= RSX_GCM_CLEAR_RED_BIT;
+		if (mask & RSX_GCM_CLEAR_ALPHA_BIT) result |= RSX_GCM_CLEAR_ALPHA_BIT;
 		return result;
 	}
 
@@ -767,6 +767,26 @@ namespace rsx
 		std::swap(red, blue);
 	}
 
+	static inline u32 get_b8_clearmask(u32 mask)
+	{
+		u32 result = 0;
+		if (mask & RSX_GCM_CLEAR_BLUE_BIT) result |= RSX_GCM_CLEAR_RED_BIT;
+		return result;
+	}
+
+	static inline void get_b8_colormask(bool& red, bool& green, bool& blue, bool& alpha)
+	{
+		red = blue;
+		green = false;
+		blue = false;
+		alpha = false;
+	}
+
+	static inline void get_b8_clear_color(u8& red, u8& /*green*/, u8& blue, u8& /*alpha*/)
+	{
+		std::swap(red, blue);
+	}
+
 	static inline color4f decode_border_color(u32 colorref)
 	{
 		color4f result;