diff --git a/Tracker/TrackerRecEvent/TrackerSpacePoint/TrackerSpacePoint/FaserSCT_SpacePoint.h b/Tracker/TrackerRecEvent/TrackerSpacePoint/TrackerSpacePoint/FaserSCT_SpacePoint.h
index f21facf6ae0533bcd14a0bd29ebbc92157328d39..5c4c92cdbab1cc7ce7dac5ab36430da0c5a13a80 100755
--- a/Tracker/TrackerRecEvent/TrackerSpacePoint/TrackerSpacePoint/FaserSCT_SpacePoint.h
+++ b/Tracker/TrackerRecEvent/TrackerSpacePoint/TrackerSpacePoint/FaserSCT_SpacePoint.h
@@ -233,15 +233,15 @@ namespace Tracker
   inline double FaserSCT_SpacePoint::eta(double z0) const
   {
     //  double zr = (m_z-z0)/m_r; 
-    double zr = (m_position.z() - z0)/m_position.perp();
+    double zr = (m_position.z() - z0)/std::hypot(m_position.x(), m_position.y());
     return std::log(zr+std::sqrt(1.+zr*zr));
   }
 
   inline double FaserSCT_SpacePoint::r() const
-  { return m_position.perp(); }
+  { return std::hypot(m_position.x(), m_position.y()); }
 
   inline double FaserSCT_SpacePoint::phi() const 
-  {  return m_position.phi(); }
+  {  return std::atan2(m_position[1], m_position[0]); }
 
   // The methods required by MeasurementBase
   inline const Amg::Vector3D& FaserSCT_SpacePoint::globalPosition() const