Early in September, the Phoenix Mercury walked off the Madison Square Garden court after getting blownout by the New York Liberty. It was their third straight loss, and as a result, they were left hanging on the edge of playoff contention with just a few games remaining in the season. Still, there were many who thought the team–which features the same core that won the 2014 WNBA title–would be able to figure it out, to just flip that switch come playoff time.

A few weeks later, the GMs’ preseason pick to win the 2016 WNBA championship is on to the second round of the WNBA Playoffs after defeating the Indiana Fever in their single elimination, round one meeting. The switch was flipped. At least on Wednesday night.

The main cause for concern throughout the Mercury’s less than stellar regular season, was defense. After that ill-fated game against the Liberty early in September, the Mercury locker room was unanimous; they were capable of figuring things out come playoff time, but it started on the defensive end. As head coach Sandy Brondello put it, “we have to hang our hat on defense.”

Wednesday night in Indiana, they did just that.

When asked postgame by ESPN how the Mercury were able to pull away in that second half, DeWanna Bonner was clear: “Defense. We started playing better team defense, protecting the paint a little bit…We just went in at halftime and said we have to play better defense.”

During the regular season, the Mercury’s defensive rating was ninth in the league, as they allowed opponents to score 103.7 points per possession. On Wednesday, their defensive rating checked in at 98.7, by far the best mark of the four teams in action on this first night of the playoffs.

Over the course of the first 34 games of 2016, the Mercury were last in three-point defense, as they allowed their opponents to shoot 35.6 percent from downtown. In their first playoff game, the Mercury held the Fever to 4-for-21 from three, or 19 percent.

Throughout the regular season, the Mercury were 12-4 when they held opponents under 80 points. Wednesday night they extended that mark to 13-4, coming away with an 89-78 victory.

Yes, the Mercury had a defensive performance they could hang their hat on. And they proved the faithful right. When it matters most, they really can just flip the switch. Now, the only question that remains, is just how long can that switch remain in the “on” position?