To say the main reason Sylvia Fowles is here, in a Lynx uniform, was for this series is probably an overstatement.

But not by much.

The Lynx worked very hard during the first half of the regular season on a trade that brought the 6-6 Fowles to Minnesota just after the All-Star Game. Adding a player of her caliber is always a goal. But in pursuing Fowles, the Lynx had this matchup in mind. Namely, someone who could match up with Mercury center Brittney Griner.

The Lynx will face the Mercury in the WNBA Western Conference finals for the third consecutive year and for the fourth time in five years in a best-of-three series that starts Thursday at Target Center. And while the Fowles-Griner battle is not the only key matchup in this series, it is a very big one.

“Besides Sylvia being a great player, it’s one of the key reasons we made this trade,” Lynx coach Cheryl Reeve said. “To be able to handle ourselves in a way, inside, that is more challenging to Griner.’’

Occupying Griner could prevent her from roaming the paint blocking drives and midrange shots. At least slowing her on offense could present challenges to the Mercury.

These two teams have been battling for the top of the Western Conference for years. And it’s a rivalry that gained steam season by season. There was the opening game of the 2013 conference finals when, with the Lynx taking it to the Mercury — the Lynx would win the series in two games — Seimone Augustus and Diana Taurasi traded shoves, with Taurasi ultimately planting a kiss on Augustus’ cheek.

Or last season in a deciding Game 3 in Phoenix, when, after Augustus had helped bring the Lynx back into the game with a spectacular third quarter, Taurasi ended the quarter with a buzzer-beating, half-court bomb that took the air out of Minnesota’s comeback.

The rivalry is still intense, but it has been altered by change; Taurasi is taking the year off, as is Penny Taylor. The Lynx have new faces as well.

Griner, the league’s defensive player of the year, has taken her game to another level in the playoffs. In a two-game sweep of Tulsa, she averaged 20.5 points, 10.5 rebounds and eight blocks. To Reeve, part of that was a matchup problem for Tulsa. She says her team will do a better job defensively on the Mercury, which averaged 89.5 points per game vs. Tulsa.

And that starts with Fowles. And she knows it. Fowles’ rather quite postseason took a turn Tuesday when, in the fourth quarter, she scored nine of her 13 points after the Sparks had cut the Lynx lead to a point. This came after she had struggled, sitting for much of the second and third quarters.

“She came through for us in a big way in the fourth,’’ Reeve said. “I’d like to think that will be good momentum for her heading into this next series.’’

No pressure, right?

“It’s no pressure at my end,’’ Fowles said. “I just know what I’m capable of and what I bring to the team. You have a player who’s 6-8 who has Brittney Griner’s ability, you want to bring in somebody who can do what I do as well.’’

The two played each other fairly evenly in last year’s league finals, when Fowles was with Chicago. In three games this season the number have been close, too. In Minnesota’s Aug. 30 victory over Phoenix at Target Center, Griner outscored Fowles 13-4 in the first half, which ended with Phoenix up 39-34. But Fowles held Griner scoreless in the second half as the Lynx outscored Phoenix by 15.

Just as the two teams know each other well, Fowles and Griner do, too.

“You really have to go at her,” Fowles said. “She’s very long, very edgy and takes up a lot of space in the paint. But you have to go and be physical.’’