The formula is basic, Lynx coach Cheryl Reeve said. When it comes to winning in the playoffs — no matter the opponent — the Lynx have to be efficient on offense and defend well.

Of course that’s easier said than done when it comes to playing the Phoenix Mercury. The two teams will begin their best-of-three Western Conference finals Friday in Phoenix. They are the top two teams in the league in wins, points scored, point differential, field-goal percentage and offensive efficiency.

The difference, at least during the regular season, is that the Mercury also was the most efficient defensive team. The Lynx, dealing with injuries, were in the middle of the pack.

So the challenge is there.

“Offensive efficiency will be critical,” Reeve said. “We know we’re going to defend. We know they pose some challenges to our defense. They’re going to win some battles, as far as matchups. We can’t have any empty possessions against these guys. They’ll play some zone. They’re long. We have to really identify where our shots will come from. But we have confidence.”

In this All-Star-filled series, the Lindsay Whalen-Diana Taurasi matchup will be huge. Ditto for how the Mercury, led by DeWanna Bonner, plans on trying to slow down league MVP Maya Moore.

But here are three key matchups that are a bit below the radar, but figure to have a huge impact on the series:

Lynx G Seimone Augustus vs. Phoenix G Penny Taylor: This is a matchup, points-wise, that the Lynx absolutely have to win. Both players are looking good after injuries.

For Taylor, it wasn’t until this season that she appeared to be all the way back from a knee injury that limited her to only 10 games a year ago. She averaged 10.5 points this season, 8.0 in four games vs. the Lynx.

Augustus, meanwhile, is finally looking pain-free after dealing with knee soreness much of the season. She scored 47 points on 16-for-30 shooting in the two-game series victory over San Antonio, and she averaged 15.7 points in three games vs. Phoenix this season, missing one game because of injury.

Lynx C Janel McCarville vs. Phoenix C Brittney Griner: The Lynx don’t need McCarville to win this battle statistically. They do, however, need her to control Griner, keeping the 6-8 center out of her comfort zone at both ends of the court.

“You can’t let her get inside position,’’ McCarville said. “You have to fight her up the court the whole way, make her work on defense as well.”

In her second season, Griner has come into her own. The league’s Defensive Player of the Year, she set a WNBA record with 129 blocks to go with 15.6 points and 8.0 rebounds per game.

The Mercury uses its defense to funnel action to Griner, who defends the rim better than anyone in the league. She had her best game this season in the Mercury’s 92-79 victory over the Lynx on June 18, when she scored 27 points with 18 rebounds.

Lynx F Rebekkah Brunson vs. Phoenix F Candice Dupree: Dupree is the third-leading scorer on her team, but nobody takes more shots. She averaged 14.5 points and 7.6 rebounds per game while shooting 53.3 percent.

Brunson is still perhaps not all the way back from preseason knee surgery. But she is still the team’s best defender. It should be noted that Dupree averaged 18.5 points on 54 percent shooting vs. the Lynx in the two games Brunson missed. But in the final two meetings — the Lynx won one and were within a possession of winning the other on the road — Dupree averaged only 8.0 points and shot 34.8 percent.

“It’s a pivotal matchup for us,” Reeve said. “She takes the most shots on that team, and we have our best defender on her. That should be fun to watch.”


• Lynx rookie forward/center Damiris Dantas might have to return to Brazil to tend to a family matter. More will be known about the situation, which kept Dantas out of Wednesday’s practice, on Thursday.