diff --git a/src/gromacs/ramd/ramd.cpp b/src/gromacs/ramd/ramd.cpp
index 0a6cbc8baf..241c17dac9 100644
--- a/src/gromacs/ramd/ramd.cpp
+++ b/src/gromacs/ramd/ramd.cpp
@@ -229,8 +229,8 @@ void RAMD::calculateForces(const ForceProviderInput& forceProviderInput,
     {
         for (int i = 0; i < 3; ++i)
         {
-            get_pull_coord_value(pull, g * 2 + i, &pbc);
-            apply_external_pull_coord_force(pull, g * 2 + i, direction[g][i] * params.group[g].force,
+            get_pull_coord_value(pull, g * 3 + i, &pbc);
+            apply_external_pull_coord_force(pull, g * 3 + i, direction[g][i] * params.group[g].force,
                 &forceProviderInput.mdatoms_, &forceProviderOutput->forceWithVirial_);
         }
     }