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Thirteen-year veteran Katie Smith turned into the "Katie of old" to help the Seattle Storm clinch the Western Conference's No. 2 seed.

Smith scored 11 of her season-high 26 points in the third quarter to lead the Storm past Phoenix, 85-70 on Friday night and clinch home-court advantage against the Mercury in the playoffs next week.

"That was Katie of old right there," said Phoenix guard Diana Taurasi, who scored a season-high 36 points. "That's a young Katie. She could probably do that more often, but she's willing to divert the last couple of years because she's been on some talented teams. Katie could probably do that every night."

Tanisha Wright added 18 points and Sue Bird 15 for Seattle (20-13), which has the tiebreaker against Phoenix (19-14) for the No. 2 playoff seed in the Western Conference with one game remaining. The Storm won the season series 3-1.

Smith, in her first year with the Storm, used the shooting of Taurasi for motivation.

"Yeah, I let her know, come on now you're still the baby in all of this," Smith said. "She's younger, but she's one of my favorite players to play against and to play with on Olympic teams. I have much respect for her and I know she does, too. We have a lot of fun competing against each other and it's been a friendly rivalry now for many years."

Taurasi had 28 in the first half, three shy of the WNBA record, to help the Mercury to a 41-35 lead. But after tying a league record with six 3-pointers in the first half, she did not make one in the second.

Phoenix opens the best-of-three series Thursday at Seattle, which has won seven of eight.

Smith came into the game averaging 6.6 points with a season high of 16, against Phoenix Aug. 16. She moved within two of scoring 6,000 career points.

Smith mixed in a few drives with her long-range shots.

"The minute she checked in the game it was an aggressive Katie," Bird said. "She came out driving to the basket, getting a couple of layups and opened up things for her from the 3-point line. You could tell she was just in a little bit of a comfort zone.

"I know in my head I was thinking we should milk it because she was feeling good out there and I tried to get her the ball as much as possible."

Le'coe Willingham, Wright and Bird hit 3-pointers and Bird made two free throws to give Seattle a 69-58 lead with 5:45 left in the game. The Mercury never threatened again.

"We kind of let up in the second half," said Mercury forward Candice Dupree. "I thought we did a decent job on defense, but our offense got a little stagnant late in the third and early fourth quarter. We can't let that happen."

Smith scored 11 straight, including three 3-pointers, in the third quarter to help rally the Storm from a nine-point deficit. Seattle led 58-56 after three quarters.

Taurasi scored 20 in the second quarter, two shy of the league record she set in 2006. She had 12 during a 16-4 run to give the Mercury a six-point lead after trailing 31-25.

Smith scored 15 in the first half and had 12 to help give the Storm a 21-15 lead after one quarter. She was 4 of 4 from the field, including a 3-poiner and three-point play in the opening period.

Seattle is 7-1 since Lauren Jackson returned after missing 20 games with a hip injury, although Jackson had only four points and did not score until the fourth quarter.

The Storm improved to 14-2 at home. Phoenix dropped to 8-9 on the road.

Phoenix played without Penny Taylor, who has missed four of the last five games with muscle spasms. Taylor averages 16.7 points.

NBA Hall of Famer Bill Russell watched the game from a front-row seat and received a standing ovation when introduced to the crowd. Russell lives on nearby Mercer Island.