diff --git a/dune/solvers/iterationsteps/obstacletnnmgstep.hh b/dune/solvers/iterationsteps/obstacletnnmgstep.hh
index 41e89e07281031238f78b71520a3b8fac9713682..2a6f0f9b21f1a2075cb9fd25b8538102deee5639 100644
--- a/dune/solvers/iterationsteps/obstacletnnmgstep.hh
+++ b/dune/solvers/iterationsteps/obstacletnnmgstep.hh
@@ -274,9 +274,12 @@ class ObstacleTNNMGStep
 
                 for (int j = 0; j < blockSize; ++j)
                 {
+                    auto const inverseCoarseCorrection =
+                        field_type(1) / coarseCorrection_[i][j];
+
                     // compute relative defect constraints
-                    defectConstraint.lower(j) /= coarseCorrection_[i][j];
-                    defectConstraint.upper(j) /= coarseCorrection_[i][j];
+                    defectConstraint.lower(j) *= inverseCoarseCorrection;
+                    defectConstraint.upper(j) *= inverseCoarseCorrection;
 
                     // orient relative defect constraints
                     if (defectConstraint.lower(j) > defectConstraint.upper(j))