diff --git a/GPU/Directx9/ShaderManagerDX9.cpp b/GPU/Directx9/ShaderManagerDX9.cpp
index 3282154550..fd38cf3c05 100644
--- a/GPU/Directx9/ShaderManagerDX9.cpp
+++ b/GPU/Directx9/ShaderManagerDX9.cpp
@@ -306,6 +306,38 @@ void ShaderManagerDX9::VSUpdateUniforms(int dirtyUniforms) {
 			flippedMatrix[12] = -flippedMatrix[12];
 		}
 
+		// In Phantasy Star Portable 2, depth range sometimes goes negative and is clamped by glDepthRange to 0,
+		// causing graphics clipping glitch (issue #1788). This hack modifies the projection matrix to work around it.
+		if (g_Config.bDepthRangeHack) {
+			float zScale = getFloat24(gstate.viewportz1) / 65535.0f;
+			float zOff = getFloat24(gstate.viewportz2) / 65535.0f;
+
+			// if far depth range < 0
+			if (zOff + zScale < 0.0f) {
+				// if perspective projection
+				if (flippedMatrix[11] < 0.0f) {
+					float depthMax = gstate.getDepthRangeMax() / 65535.0f;
+					float depthMin = gstate.getDepthRangeMin() / 65535.0f;
+
+					float a = flippedMatrix[10];
+					float b = flippedMatrix[14];
+
+					float n = b / (a - 1.0f);
+					float f = b / (a + 1.0f);
+
+					f = (n * f) / (n + ((zOff + zScale) * (n - f) / (depthMax - depthMin)));
+
+					a = (n + f) / (n - f);
+					b = (2.0f * n * f) / (n - f);
+
+					if (!my_isnan(a) && !my_isnan(b)) {
+						flippedMatrix[10] = a;
+						flippedMatrix[14] = b;
+					}
+				}
+			}
+		}
+
 		const bool invertedZ = gstate_c.vpDepth < 0;
 		ConvertProjMatrixToD3D(flippedMatrix, invertedX, invertedY, invertedZ);