Yeh there is, book 8 is the Phaeacian games.
Although there is the conflict between Odysseus and a Phaeacian noble, the passage serves as a respite from the sufferings of Odysseus, and as further demonstration of his physical prowess. As well as this there is the dance routine demonstrated at the command of Alcinous, which ultimately has no bearing on the plot. However, the need for Odysseus to help spread the fame of the Phaeacians is evident and highlights their isolation from the rest of the world. Thus it acts primarily to show a level of exchange in the process of guest friendship, the Phaeacians need Odysseus to spread their kleos just as much as Odysseus needs them to complete his nostos. It also helps introduce Odysseus to us from a 3rd person perspective, who we will later have to learn about from primarily first person accounts of his wanderings. Thus his rage with the Phaeacian who challenged him and dutifully beating him can be seen as a precursor for the revenge upon the suitors.
Similarly, the funeral games of book 5 of the Aeneid offer a period of joy in comparison to Aeneas' sufferings in the preceeding 4 books. They are full of references that the Roman audience could have related to, as they were frequent spectators of games, in fact funeral games were a regular custom, and Aeneas' holding of the games is likely to reference Augustus' games for his 'father' Julius Caesar. The games in the Aeneid serve the purpose of showing us Aerneas' character in dealing with his men, he is shown to be loyal and compassionate and fair; he rewards even those who don't win, and in the case of the archery competition even goes as far as to give prizes for those who completely failed or had no chance of winning such as Acestes. Although the games have a jocular tone, such as the helmsman from one boat being thrown overboard by the captain, they are definately not arbitrary. All the above contributes to setting the scene for when the Trojans go to war in the latter half of the poem, nowehere is this more evident than where Nisus throws himself under another run so that Euryalus might win. However the mood quickly turns owing to the contrivances of Juno and we are swiftly returned to the negative pessimistic overtones of the rest of the poem when the women burn the boats.
Overall both in the Odyssey and the Aeneid the author uses these brief divergences from the advancement of plot to provide relief from the narrative. They also are both used to importantly explain the situation of the protagonists and set the scene for later episodes.