It's the first time that's happened since 2011. The Mystics will try and win the title after getting swept in the finals last season, while the Sun return to the championship for the first time since 2005.
It's the third time since the WNBA changed its playoff format in 2016 that the top two seeds advanced to play for the title. Washington, as a three-seed last year, is the only team not to finish 1 or 2 in the regular-season standings to reach the championship round.
Here are a few things to watch for in the WNBA Finals:
EASTERN DOMINANCE: Even though there really aren't conferences in the WNBA since the playoff format change in 2016, the former East will have the champion. It's only the second time since 2009 that an Eastern team will win. The Indiana Fever were champions in 2012. Since the league's first championship in 1997, the East has won four titles (three by Detroit and Indiana's).
TOUGH TERPS: Maryland will be well represented in the finals with five of coach Brenda Frese's former players competing. Washington has Shatori Walker-Kimbrough ('17), Tianna Hawkins ('13) and Kristi Toliver ('09) while the Mystics feature Brionna Jones ('17) and Alyssa Thomas ('14). Washington also has Kiara Leslie, who played two years at Maryland before transferring to N.C. State for her final two seasons. She hasn't played this year because of a knee injury.
Only Toliver won a championship in college and she's also the only one to win a WNBA title, doing so with Los Angeles in 2016.
DISREPECTED: The Connecticut Sun have relished playing the role of the underdog lately. The team, despite finishing second, had no players win major WNBA awards. The Sun have been selling T-shirts during their playoff run that read DisrespeCT with the CT highlighted.
''I just don't think people have been paying attention to how we've played all season,'' said forward Alyssa Thomas, one of four Sun players who average in double digits. ''We are a No. 2 seed for a reason. And for no one to pick us and just assume that we are not a team that can't play in the playoffs, we took that to heart.''
FULL STRENGTH: The Mystics lost two of the three meetings with Connecticut during the regular season, but Washington was without key members of its team in all three games. Elena Delle Donne missed the first game on May 25 because of knee pain. Emma Meesseman missed the other two games because she was with the Belgium national team.
FAMILIAR FACE: Winning the best-of-five series would give coach Mike Thibault his first championship. It would come against his former team, which he led from 2003-12. Thibault, who turns 69 on Saturday, guided the Sun to the WNBA Finals in 2004 and 2005 before they fell short each time.
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