A widely supported formation scenario for the Galactic disc is that
it formed inside-out from material accumulated via accretion events.
The Sagittarius dwarf spheroidal galaxy (Sgr dSph) is the best example
of a such accretion, and its ongoing disruption has resulted in
that its stars are being deposited in the Milky Way halo and outer
disc. It is therefore appealing to search for
possible signatures of the Sgr dSph contribution to the build-up of the
Galactic disc. Interestingly, models of the Sgr dSph stream indicate
clearly that the trailing tail passes through the outer Galactic
disc, at the same galactocentric distance as some anti-centre
old open star clusters. We investigate in this Letter the possibility
that the two outermost old open clusters, Berkeley 29 and Saurer 1,
could have formed inside the Sgr dSph and then left behind
in the outer Galactic disc as a result of tidal interaction with
the Milky Way. The actual location of these two star clusters,
inside the Sgr dSph trailing
tail, is compatible with this scenario, and their chemical and
kinematical properties, together with our present understanding
of the age-metallicity relationship in the Sgr dSph, lends further
support to this possible association. Hence, we find it
likely that the old open star clusters Berkeley 29 and Saurer 1
have extra-galactic origins.