Larry Reynolds understands why the Diamondbacks are shopping his client, Justin Upton, but the agent is upset over attacks leveled at the outfielder's character. "Justin wants to stay, but I know trade rumors and trades are part of the business," Reynolds told USA TODAY. "What I don't like are the comments and innuendos made about Justin's work ethic and character, especially from those gutless people that don't want to put their name by a quote. "This young man is one of the hardest workers I've been around and more importantly, he's a good person. If they want to trade him, that's their business, just knock off the unfounded, negative rhetoric." Diamondbacks general manager Kevin Towers has informed teams he'll listen to trade proposals for Upton. He says he's also upset by unattributed comments attacking Upton, the 24-year-old who is hitting .264 with seven home runs and 37 RBI. "You should have enough issues with your own club without talking about somebody else," Towers said of personnel from other teams attacking Upton.