PHOENIX -- In Monday's postgame press conference, D-backs manager Kirk Gibson playfully referred to Ryan Roberts this way:

"He's good and he's a knucklehead, too," Gibson said. "Reminds me a lot of his manager."

In the 3-0 win over the Brewers, Roberts hit his 13th home run of the year and second in as many days. It was the second time this year he's homered in consecutive days.

He's 4-for-9 since the All-Star break and has hit safely in each start during that span.

"I was just struggling right before the break," he said. "I wasn't tired, I didn't feel like I needed a break, but it did obviously help to rest the body.

"It was just one of those moments in baseball where it wasn't going right for me."

The 30-year-old infielder is hitting .263 with 40 RBIs and 13 stolen bases entering Tuesday's game.

"He's so anxious to do right and do well that he takes everything you say," Gibson said. "He doesn't take it with a grain of salt, he really takes it to heart and sometimes looks a little further than what it is.

"I can relate to that. I love his eagerness, his desire, determination and the way he plays."

Roberts hit leadoff and started at third base on Tuesday.

Duke ready to help D-backs out of bullpen

PHOENIX -- Zach Duke knows his role.

"My job is to get guys out when I have the opportunity to get them out," the D-backs left-hander said on Tuesday.

"I'm just going to try to help this team win games any way that I can."

And with the recent callup of Barry Enright to fill out the back end of the rotation, Duke, a starter by trade, will get his first experience in the bullpen.

"It's a new challenge," he said. "It will be a different experience."

The 28-year-old has struggled in a starting role this year with a 2-4 record and a 5.47 ERA in nine starts. His D-backs tenure began in late May after he injured his pitching hand on a line-drive comebacker in Spring Training.

D-backs manager Kirk Gibson said he was unsure of the role Duke will fill, but could see him used in both long relief and special left-handed situations.

"He's gotten left-handers out better than he has right-handers," Gibson said. "But we could use him in long relief, obviously. He would give us some length."

Duke, who hasn't pitched since the All-Star break, said he has been preparing the same as he would if he were starting.

"I just prepare everyday to be ready to pitch," he said. "That way, whenever the phone rings and it's my time, I'm prepared to give everything I've got."

Gibson can relate to Heilman's situation

PHOENIX -- D-backs manager Kirk Gibson was released in 1992, a month into the season as a member of the Pittsburgh Pirates.

"There's no easy way, there's no joy to it," he said. "It stinks."

Which is why it was tough to release reliever Aaron Heilman after Monday night's victory.

"I remember what Aaron did for us last year, as well as the effort he put in this year," Gibson said. "He gave 100 percent effort all the time, it's just one of those deals and the way the game moves sometimes."

Heilman, 32, went 4-1 with a 6.88 ERA (27 earned runs in 35 1/3 innings) with 11 walks and 33 strikeouts in 32 games with the D-backs this season. He joined Arizona last year after one season with the Cubs and six with the Mets, the team that drafted him in 2001.

"I knew exactly how he felt," Gibson said. "But I encouraged him to believe in himself and that maybe there was a better opportunity, maybe it will help his career."

Gibson's 1992 release helped him, as he played three productive seasons in Detroit after that to finish his career.

"I'm sure he'll draw some interest," he said. "He throws the ball fine, he just hasn't had a good year for us."