  The Chekanov torus was the first known \emph{exotic} torus, a monotone
Lagrangian torus that is not Hamiltonian isotopic to the standard monotone
Lagrangian torus. We explore the relationship between the Chekanov torus in
$S^2 \times S^2$ and a monotone Lagrangian torus which had been introduced
before Chekanov's construction \cite{Chekanov}. We prove that the monotone
Lagrangian torus fiber in a certain Gelfand--Zeitlin system is Hamiltonian
isotopic to the Chekanov torus in $S^2 \times S^2$.
