Willie Mitchell won't be back with the Los Angeles Kings next season. The 37-year-old rearguard will test the market as an unrestricted free agent next week. The Kings have six defensemen who are signed for at least the 2014-15 campaign, with Jake Muzzin, Drew Doughty, Robyn Regehr, Slava Voynov, Alec Martinez and Matt Greene patrolling the back end. Mitchell is also seeking a two-year deal, which Los Angeles couldn't accommodate.