The Guardian of the Gate (later dubbed Pablo the Blue Knight) is an overprotective knight who stands in front of a gate leading to King Austin's castle. He did not know how to open the gate for a period of time.
The Guardian of the Gate is mostly blue. He wears a white and blue-striped squire's dress. On the front of the stripes are fleur-de-lis patterns.
Pablo has played the Guardian of the Gate in one episode of The Backyardigans: "Knights Are Brave and Strong" from season one. Pablo also wears the guardian's knight outfit as a disguise in "Le Master of Disguise" from season three.