diff --git a/opm/simulators/wells/StandardWellEquations.cpp b/opm/simulators/wells/StandardWellEquations.cpp
index 67e0b1464..91d9876e5 100644
--- a/opm/simulators/wells/StandardWellEquations.cpp
+++ b/opm/simulators/wells/StandardWellEquations.cpp
@@ -130,6 +130,17 @@ void StandardWellEquations<Scalar,numEq>::apply(const BVector& x, BVector& Ax) c
     duneC_.mmtv(invDBx, Ax);
 }
 
+template<class Scalar, int numEq>
+void StandardWellEquations<Scalar,numEq>::apply(BVector& r) const
+{
+    assert(invDrw_.size() == invDuneD_.N());
+
+    // invDrw_ = invDuneD_ * resWell_
+    invDuneD_.mv(resWell_, invDrw_);
+    // r = r - duneC_^T * invDrw_
+    duneC_.mmtv(invDrw_, r);
+}
+
 #define INSTANCE(N) \
 template class StandardWellEquations<double,N>;
 
diff --git a/opm/simulators/wells/StandardWellEquations.hpp b/opm/simulators/wells/StandardWellEquations.hpp
index 4bf09e8e2..f63baca3d 100644
--- a/opm/simulators/wells/StandardWellEquations.hpp
+++ b/opm/simulators/wells/StandardWellEquations.hpp
@@ -76,6 +76,9 @@ public:
     //! \brief Apply linear operator to vector.
     void apply(const BVector& x, BVector& Ax) const;
 
+    //! \brief Apply linear operator to vector.
+    void apply(BVector& r) const;
+
     // two off-diagonal matrices
     OffDiagMatWell duneB_;
     OffDiagMatWell duneC_;
diff --git a/opm/simulators/wells/StandardWell_impl.hpp b/opm/simulators/wells/StandardWell_impl.hpp
index 47d18e284..16a33b1e9 100644
--- a/opm/simulators/wells/StandardWell_impl.hpp
+++ b/opm/simulators/wells/StandardWell_impl.hpp
@@ -1736,12 +1736,7 @@ namespace Opm
     {
         if (!this->isOperableAndSolvable() && !this->wellIsStopped()) return;
 
-        assert(this->linSys_.invDrw_.size() == this->linSys_.invDuneD_.N());
-
-        // invDrw_ = invDuneD_ * resWell_
-        this->linSys_.invDuneD_.mv(this->linSys_.resWell_, this->linSys_.invDrw_);
-        // r = r - duneC_^T * invDrw_
-        this->linSys_.duneC_.mmtv(this->linSys_.invDrw_, r);
+        this->linSys_.apply(r);
     }
 
     template<typename TypeTag>