Near the end of this episode Marshall comes into the bar and is saying that he is going to fight the gay guy, and then the guy tells him he's gay, and Marshall says he has never been in a fight before. But in episode
4.10 - The Fight, Marshall says he's been in plenty of fights.
After Lily takes off her engagement ring to try and attract a pass, she is seen talking to Robin wearing her ring. It then disappears when the gay guy comes up to tell her she sat on a grape and she pulls it out of her pocket to show him.