In Sophocles' Oedipus the King, besides the predictions of Teiresias, what other foreshadowing of the shepherd's revelation does the play contain?

Throughout Sophocles' Oedipus the
King, the playwright gives the audience several glimpses and recollections
that Oedipus has, indeed, killed his father and married his
mother.

Early in the play, before Teiresias arrives, Creon
recalls for Oedipus what he knows about the death of Laius. Oedipus learns from Creon
that Laius' death was murdered, that Laius was on his way to Delphi when it happened,
and that only one person from Laius' entourage escaped death. According to that person,
however, Laius and company were attacked by multiple robbers and not one
person.

Also, before Teiresias arrives, Oedipus questions
the old men of Thebes (i.e., the Chorus) about Laius' death. They also report that
"Laius was killed by certain travellers" (Ian Johnston
translation).

Later, when Oedipus accuses Creon of
conspiring against him, Creon reveals that it has been many years since Laius' murder
occurred, thus providing another clue that would link Oedipus to the
crime.

When Jocasta comes on stage to calm the dispute
between Creon and Oedipus, she provides further information about Laius' death.
Jocasta's information about the murder occurring "at a place where three roads meet"
provides an additional detail that causes Oedipus to become quite worried. Furthermore,
she specifies that the murder occurred just before Oedipus became king of Thebes. She
also adds additional detail about the number of men Laius had with him at the time of
his death.

After Oedipus hears Jocasta's account of Laius'
death, he recalls his own bloody encounter with a man and his entourage at "a spot where
three roads meet". Still, Oedipus is not completely certain that he was Laius' killer
because of the persistent report that Laius was killed by multiple persons and not one
solitary person.

So, other than the comments by Teiresias
and prior to the arrival of the two shepherds, Sophocles provides the audience with
plenty of indications that Oedipus is Laius' killer. In fact, it appears that each
person that comes on stage with Oedipus provides him with some bit of information about
Laius' death. Oedipus' only stumbling block to piecing together the mystery is the
account that Laius was killed by multiple attackers.