Former Diamondbacks general manager Dave Stewart has returned to his family-run agency – Sports Management Partners – which he’ll operate with his wife, Lonnie Murray, according to Bob Nightengale of USA Today (Twitter link). Stewart previously represented Matt Kemp and Chris Carter, among others, but he had to leave the business when the D-backs hired him in 2014. The fact that Murray remained with the agency while Stewart served as a GM led to conflict-of-interest questions, as Nick Piecoro of the Arizona Republic detailed last March. Now for a few updates on notable agency changes that have happened this week: One year before he’s scheduled to hit the open market, Rays right-hander Alex Cobb has switched agencies from ACES to Beverly Hills Sports Council, tweets Marc Topkin of the Tampa Bay Times. Cobb was a high-end starter from 2013-14, but he missed all of 2015 thanks to Tommy John surgery and posted ugly results in his return last season. Over an admittedly small sample size (22 innings), the 29-year-old logged an 8.59 ERA to go with 6.55 K/9 – his lowest since 2011.