diff --git a/ProcessLib/SmallDeformation/Tests.cmake b/ProcessLib/SmallDeformation/Tests.cmake
index 7089559cf0603f9aa7427a54a099f3d214306b91..7f181bf55c5c9d9e2aa2d2412ea81c47459c791b 100644
--- a/ProcessLib/SmallDeformation/Tests.cmake
+++ b/ProcessLib/SmallDeformation/Tests.cmake
@@ -112,7 +112,9 @@ if (OGS_USE_MFRONT)
         PROPERTIES PASS_REGULAR_EXPRESSION "The nonlinear solver failed in time step #.* at t = 5.37.* s for process #0"
     )
     OgsTest(PROJECTFILE Mechanics/MohrCoulombAbboSloan/load_test_mc.prj)
-    OgsTest(WRAPPER mpirun -np 4 PROJECTFILE Mechanics/MohrCoulombAbboSloan/PetscMpi/slope_hexa.prj)
+    if (OGS_USE_MPI)
+        OgsTest(WRAPPER mpirun -np 4 PROJECTFILE Mechanics/MohrCoulombAbboSloan/PetscMpi/slope_hexa.prj)
+    endif()
     OgsTest(PROJECTFILE Mechanics/MohrCoulombAbboSloanAnisotropic/triax_1e0_47.prj)
     OgsTest(PROJECTFILE Mechanics/MohrCoulombAbboSloanAnisotropic/triax_ortho_1e0_47.prj)
     OgsTest(PROJECTFILE Mechanics/MohrCoulombAbboSloanAnisotropic/triax_aniso_1e0_47.prj)