PHOENIX (AP) -- The Phoenix Mercury fired coach and general manager Corey Gaines on Thursday after a five-year run that included a WNBA title but a disappointing 2013 season.
Former University of Arizona coach Russ Pennell will serve as interim coach and President and CEO Amber Cox will be interim GM.
Phoenix went into this season with high expectations after adding No. 1 overall draft pick Brittney Griner to a roster that featured star players Diana Taurasi, Penny Taylor and Candice Dupree.
Phoenix won eight of nine games after a slow start to the season, but has lost seven of nine to fall 7 1-2 games behind Minnesota in the Western Conference at 10-11.
"First and foremost, we thank Corey for his years of dedication to this franchise, its players and its fans," Cox said in a statement. "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."
Gaines was an assistant under Paul Westhead, his former coach at Loyola Marymount, when the Mercury won the 2007 WNBA title and led them to another championship in his first season as head coach in 2009.
Phoenix struggled last season, thanks in large part to a slew of injuries, and wound up with the top pick in this year's draft.
They used it on Griner, a 6-foot-8 dunking sensation who dominated college basketball while at Baylor.
So, far, the rookie center hasn't been the overpowering force so many had predicted, plagued by injuries while trying to mesh with the up-tempo Mercury.
Griner leads the league with 3.0 blocked shots per game and is fourth on the team with 13.9 points while averaging 5.9 rebounds. She has missed five games this season and twisted her ankle in the Mercury's last game, Tuesday against Seattle.
Taurasi, a former league MVP, leads the WNBA with 21.4 points per game, but the Mercury have struggled defensively at times this season.
Gaines added GM duties after the 2011 season and passed Cheryl Miller on Phoenix's all-time wins list last year. He was 90-101 as head coach.
Pennell served as Arizona's interim coach in 2008-09 after Lute Olsen retired and spent four seasons at Grand Canyon University, where he went 72-44.