diff --git a/Grid/qcd/action/pseudofermion/ExactOneFlavourRatio.h b/Grid/qcd/action/pseudofermion/ExactOneFlavourRatio.h
index 9c1e2921..65f289bf 100644
--- a/Grid/qcd/action/pseudofermion/ExactOneFlavourRatio.h
+++ b/Grid/qcd/action/pseudofermion/ExactOneFlavourRatio.h
@@ -244,7 +244,7 @@ namespace QCD{
         Lop.Dtilde(spProj_Phi, Chi);
         G5R5(g5_R5_Chi, Chi);
         Lop.MDeriv(force, g5_R5_Chi, Chi, DaggerNo);
-        dSdU = Lop.k * force;
+        dSdU = -Lop.k * force;
 
         // RH: dSdU = dSdU - k \chi_{R}^{\dagger} \gamma_{5} R_{5} ( \partial_{x,\mu} D_{w} ) \chi_{}
         //     \chi_{R} = ( H(mb) - \Delta_{+}(mf,mb) P_{+} )^{-1} \Omega_{+} P_{+} \Phi
@@ -256,7 +256,7 @@ namespace QCD{
         Rop.Dtilde(spProj_Phi, Chi);
         G5R5(g5_R5_Chi, Chi);
         Lop.MDeriv(force, g5_R5_Chi, Chi, DaggerNo);
-        dSdU = dSdU - Rop.k * force;
+        dSdU = dSdU + Rop.k * force;
       };
   };
 }}