The Phoenix Mercury have relieved Corey Gaines of his duties as head coach and general manager.

The Mercury named Russ Pennell interim head coach. President and CEO Amber Cox will be interim GM.

"First and foremost, we thank Corey for his years of dedication to this franchise, its players and its fans," said Cox. "Corey helped bring two championships to our organization and for that we will be forever grateful. Unfortunately, our team's performance this season has not lived up to our expectations, and at this time, a change was necessary. Russ Pennell is a proven leader and winner, whose resume speaks to his ability to build a winning culture founded in discipline and fundamentals."

Phoenix, which selected Brittney Griner with the No. 1 overall pick in this year's draft, has struggled to a 10-11 record.

Gaines, who took over as head coach in 2008, led the team to its second WNBA title in 2009. His 90 regular-season wins are a franchise record, as are his 11 career playoff victories.

The 52-year-old Pennell brings nearly 30 years of coaching experience to his new role with the Mercury, including the last 15 years in the state of Arizona at Arizona State University (assistant, 1998-2004), the University of Arizona (head coach, 2008-09) and most recently at Phoenix's Grand Canyon University (head coach, 2009-13).