In Cannon, Anakin Skywalker and Obi-Wan Kenobi's first encounter with the Saj Ventress takes place in 22BBY during a mission to Kato Namoria in the novel Brotherhood. In Legends, however, Ventress first encountered Skywalker during their duel in Yavin 4 in the 2003 Legends Clone Wars animated series. Although Anakin Ventress's duel in Yavin 4 has only appeared in Legends, the duel may still actually be considered canon. Brotherhood author Mike Chen revealed that in the novel, Anakin mentions fighting other agents of Duku by that point in 22BBY. And that fans can infer that as a reference to Anakin and Asaj's Yavin 4 duel, as Chen explained, the duel can still have happened in canon, since Skywalker was unable to see that his opponent was ventrous because of the rain and darkness around them. Additionally, in Brotherhood, Skywalker also notes that he thinks he has seen Ventress's fan blade starfighter before, and Ventress even displays a familiarity with him by revealing that she knows his name, much to Skywalker's surprise. Brotherhood was such a fantastic novel, and this is just one more reason to appreciate it.