It’s the old adage: Defense wins championships.

It’s what Russ Pennell has preached since he was named interim head coach following the dismissal of then head coach and general manager Corey Gaines.

“When we’ve defended, we’re good; and when we don’t, we’re average,” Pennell said.

In the 13 games he’s coached, the Mercury are 9-4 holding teams to 73.2 points per game on 38.1 percent shooting, the best opponent field goal percentage in the league since August 9.

Before his hire, the Mercury were 10-11 allowing 84.7 points per game and 42.8 percent shooting.

Defense will again be the focus in the Mercury’s first round playoff series against the L.A. Sparks (24-10), according to Pennell.

“You just can’t let them do what they want to do,” he said of the Sparks. “You got to disrupt their timing. You got to get them out of their score zones, their comfort zones; and you got to turn them into a one-on-one team. When they’re moving the basketball and running their sets, they’re really good.”

The best-of-three series opens in L.A. Thursday.

“As a fan, I would see (the matchup) being really intriguing. A lot of great talent on the court and two teams who have really found their identities and they’re playing good basketball,” Diana Taurasi said. “We just have to concentrate on every little thing and focus for the whole game and we can live with whatever happens.”

The Mercury and Sparks split their four regular season meetings. L.A. won the most recent matchup, 89-55 in the season finale Sunday.

However, for the Mercury that was their sixth game in nine days and they played without Candice Dupree (hamstring) while Taurasi was limited after taking a knee to the thigh in the second quarter.

“After that (first quarter), we just kind of pulled the plug and tried to get through it. It wasn’t pretty,” said Pennell, who expects to have a full complement of players for game one.

The Mercury had won five of six before the 34-point defeat, their worst loss of the season.

“We feel good right now,” Taurasi said. “We feel good about the things we’ve been doing over the last month. We’ve tried to get better every single game, every practice.”

High expectations were placed on this team before the season began. Now, as the postseason begins, those same expectations remain.

“This team is so talented,” Pennell said. “If they catch fire at the right time, which I do think we’ve been playing pretty well, I think they can make some noise in the playoffs.”

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