Zeus only plays a minor role in "The Odyssey," showing up now and then to weigh fates in his scales, giving Odysseus a bit of help or allowing Athena to help out her clever favorite. However, as far as the gods go in Homer's epic, Poseidon and Athena play a far more important role than the king of Mount Olympus.
At the beginning of his journey home from Troy, Odysseus takes pride in his own ability in overcoming the Trojans with the ruse of the wooden horse. Poseidon hears him and takes offense, because it was the serpent from the sea that convinced the Trojans to bring the horse filled with Greek soldiers inside the walls of the city. Later, Odysseus further enrages Poseidon by blinding his son, Polyphemus the Cyclops. The crowning irony is that while Poseidon is away at a wedding feast, Odysseus washes ashore in the land of the Phaeacians, who are the ones who take Odysseus back to Ithaca.
Athena, goddess of wisdom, loves the wily and clever Odysseus, helping him throughout the epic. Whether taking the human form of Mentor to advise Odysseus' son Telemachus or giving Odysseus the guise of an old beggar to help him trick the suitors of Penelope, Athena is clearly on Odysseus' side.