diff --git a/roofit/roofitcore/inc/RooPolyVar.h b/roofit/roofitcore/inc/RooPolyVar.h
index ff3bd3d88c7d0..4957a573f9693 100644
--- a/roofit/roofitcore/inc/RooPolyVar.h
+++ b/roofit/roofitcore/inc/RooPolyVar.h
@@ -34,7 +34,7 @@ class RooPolyVar : public RooAbsReal {
    Int_t getAnalyticalIntegral(RooArgSet &allVars, RooArgSet &analVars, const char *rangeName = nullptr) const override;
    double analyticalIntegral(Int_t code, const char *rangeName = nullptr) const override;
 
-   RooRealProxy const &x() const { return _x; }
+   RooAbsReal const &x() const { return _x.arg(); }
    RooArgList const &coefList() const { return _coefList; }
    int lowestOrder() const { return _lowestOrder; }