"We asked him about it, we gave him a couple of options, and he said he didn't think he was ready to be activated," Roenicke said. "I still don't think something's right. His velocity is still down. It's OK. For another pitcher it's probably pretty good.
"But the thing is, if we bring him with us, I don't think I can pitch him three days in a row. And face it, these guys have to be able to do things like that. I just don't know with our roster and where it is, how we would be able to do something like that, especially if he says he doesn't feel he's ready."
Henderson was 28-for-32 in save chances as the Brewers' closer last season and was supposed to reprise that role in 2014 before velocity concerns this spring prompted a switch to Francisco Rodriguez. Working in a setup role, Henderson posted a 7.14 ERA in 14 appearances before the Brewers placed him on the disabled list.
Henderson underwent shoulder surgery as a Cubs Minor Leaguer in 2008, a year before the Brewers signed him, but myriad tests this season have revealed no physical damage beyond what's customary for a 31-year-old pitcher.
"I don't think he's hurting, he just can't get back to where he feels like he's ready," Roenicke said. "He hit 94 [mph], but he was not pitching at 94."
Henderson's average fastball last season was 95.3 mph, and he routinely touched 98 mph.
Roenicke hopes that Henderson can contribute before the end of the season, but the Brewers have also been working to acquire a right-handed reliever in a trade. General manager Doug Melvin said that he made offers for a number of established arms, including San Diego's Joaquin Benoit and Boston's Koji Uehara. He also reportedly made an offer for left-hander Andrew Miller of the Red Sox, even though Milwaukee already has three lefties in its bullpen.
"I know Doug was on the phone making calls, and I know what people were asking for in return, and for me it didn't make sense," Roenicke said. "I know who they were asking for for some [relievers], and you just can't give up everything."
Teams can make trades in August, but players must clear waivers first. Relievers are often dealt after July 31.
Adam McCalvy is a reporter for MLB.com. Read his blog, Brew Beat, and follow him on Twitter at @AdamMcCalvy. Teddy Cahill is a reporter for MLB.com. Follow him on Twitter at @tedcahill. This story was not subject to the approval of Major League Baseball or its clubs.