The WNBA playoffs have arrived, and with them come a new set of matchups and storylines to watch. Will Seattle’s Sue Bird end her WNBA career with a fifth championship? Can Candace Parker and the Chicago Sky repeat? Will either the Las Vegas Aces or Connecticut Sun finally figure out how to convert regular-season success to a championship parade? (And where, exactly, would the Sun hold such a parade?)

But let’s simplify things a bit. The league certainly has: Gone are the play-in games, and it’s a traditional bracket with no reseeding. The first round follows a best-of-three format, so no more higher-seeded teams will lose their entire seasons in a single game. The only wrinkle for the higher seeds? They get the first two games at home, so if they fail to hold serve, the winner-take-all game is on the lower seed’s home court.

For each playoff series, we’ve isolated one stat to know — a factor that might well decide who advances and whose season ends prematurely — starting with the Wednesday night matchups.

No. 2 Chicago Sky vs. No. 7 New York Liberty

Key Stat: The Liberty’s strong recent form

The first Wednesday night Game 1 features the Sky hosting the Liberty. The Sky have 20 percent odds to win the WNBA title, while New York is an extreme longshot, with worse than 1 percent odds.

But this one is closer than the seasonlong stats would indicate. The Liberty finished strong, 7-3 in their last 10 games with a net rating of 6.7 (which ranked third in the WNBA over that stretch). Their overall stats are weighed down by the early absence of Marine Johannès, whose return on June 10 provided a playmaking and perimeter threat which allowed Sabrina Ionescu to thrive. The Liberty are also now the healthiest they’ve been all season, with DiDi Richards, Jocelyn Willoughby and Betnijah Laney all back from injuries.

All three games between these two teams were decided by single digits, with the Sky winning two of them. (It is worth noting the Liberty’s win came in a game Courtney Vandersloot missed.) The Sky have fewer weaknesses than any other roster in the WNBA, but Chicago certainly wants to avoid a do-or-die game at the Barclays center against a high-variance Liberty team that led the league in points from beyond the arc.

No. 1 Las Vegas Aces vs. No. 8 Phoenix Mercury

Key Stat: The Aces’ negative fourth-quarter point differential

The Aces are a co-favorite to win it all by our projection model, while the Mercury are one of three playoff teams with a championship likelihood of less than 1 percent. Naturally, it’s hard to see a path to victory for the Mercury in this one — though the head-to-head matchups, all won by Las Vegas, took place all the way back in May. Neither Tina Charles nor Diana Taurasi will play in this one — the former due to a divorce with the team, the latter due to injury. Meanwhile, Skylar Diggins-Smith, the Mercury’s best player this season, is away from the team for personal reasons.

Without those players, Phoenix squeaked into the playoffs with a 2-2 finish, and it’s going to take heightened production from Diamond DeShields, who averaged 24.5 points in those two wins, and Sophie Cunningham, who made 46.2 percent of 6.5 3-point attempts per contest over the final four games of the regular season, to give Phoenix a puncher’s chance.

As for the Aces, something to watch for is whether they let the Mercury hang around through three quarters. Though the Aces had the second-best overall net rating this season (7.7), it dropped to sixth in the league (-0.3) in the fourth quarter. Of course, Las Vegas was usually able to step it up when the score got close enough to truly elicit concern — they had the league’s No. 2 net rating when the game’s margin was within 5 points in the final five minutes — but letting big leads get whittled down and counting on a turnaround in crunch time isn’t a sustainable way to play. So in that sense, if you keep things close late, the Aces could be vulnerable.

No. 3 Connecticut Sun vs. No. 6 Dallas Wings

Key Stat: Dallas’s newfound explosive offense

Moving to the Thursday night slate, we have Connecticut facing Dallas. While the Sun finished 25-11, one game behind Chicago and Las Vegas, they were arguably the WNBA’s most impressive team during the regular season. Connecticut ranked second in both offensive and defensive efficiency, leading to the top spot in overall net rating — a primary reason why our projections have them as co-title favorites , with a 31 percent chance to win it all. (Meanwhile, Dallas is also in that extreme longshot club).

There are reasons, though, to suspect this one will go a full three games or that Dallas might even prevail. The Wings won two of three regular-season matchups with the Sun. And notably, the emergence of Teaira McCowan — finally (belatedly, in my view) installed in the starting lineup — and Marina Mabrey’s ascent have turned Dallas into an offensive juggernaut. 

After McCowan became a full-time starter on July 14, the Wings had an offensive rating of 110, second only to Las Vegas over that span. Dating back even further, to the start of July, McCowan has shot 60 percent from the field while averaging close to a double-double, 15.9 points and 9.8 rebounds per game. And over her final seven games, Mabrey put up 20.9 points per game on 48.2 percent shooting, including 41.5 percent from 3-point range. The Sun present no shortage of matchup problems, from reigning MVP Jonquel Jones to human cannonball Alyssa Thomas and the league’s best Sixth Player, Bri Jones. But Dallas presents its own challenges.

No. 4 Seattle Storm vs. No. 5 Washington Mystics

Key Stat: Whoever takes the last shot

In a “pick’em” series, we finally, finally get to see a healthy Breanna Stewart and the Storm take on a healthy Elena Delle Donne and the Mystics, a gift from the basketball gods. These two teams are evenly matched: The Storm finished just ahead of the Mystics in regular-season net rating, 5.2 to 5.1, but the Storm are the No. 4 seed, meaning Seattle gets those precious first two home games. That’s the primary reason we have Seattle as 12 percent likely to win it all, with Washington at just 4 percent. 

The two teams last played in the final weekend in July, splitting two games with a final point total of Seattle 157, Washington 155. So expect a series that goes down to the final possession, and maybe even a clinching shot by either Delle Donne or Stewart. You cannot ask for more than this from a first-round series.

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