Already this season, Guillen showed a commitment to closer Heath Bell and right fielder Giancarlo Stanton when they were respectively scuffling.
"Same way with Bell. Same way we do with everybody," Guillen said. "Stanton was struggling early. Go play. The only way to come out [of the slump] is play and try to get out as quick as you can. As long as he's here, he'll play."
Buck is hitting .164 with four home runs and 13 RBIs. He ended an 0-for-26 slide a few days ago.
"I've gone through the stage of being hard on myself for where I'm at," Buck said. "I've come to terms, I've stunk. I'm going to own the average I have right now. The thing is, I know it has zero affect if I get a hit today or not."
Buck understands things can turn around at any time. Rather than dwell, he's focused on getting quality at-bats on the day he's playing.
About two weeks ago, Buck came in early and worked with Andre Dawson, a team special assistant, as well as hitting coach Eduardo Perez.
"Hawk called me early one day," Buck said of the conversation with Dawson. "He said, 'Show up to the field.' I was, 'Who is this?' 'It's Hawk.' I was like, 'All right, I'll be there.'
"I showed up, worked with him, worked my legs a little peace of mind. I've felt from there, I've really had better at-bats, walks."
A major reason Buck is in the lineup is because of the way he's handled the pitching staff.
Guillen is blunt in his assessment of Buck's hitting.
"Very bad," the manager said. "Just being honest. He's a little lost at the plate. We're working today on little things. He continues to work. But it seem likes he's worried too much, thinking too much. He should be, 'See the ball, hit the ball.' We work early on hitting.
"I think he's a way better hitter than he's showing right now. I wish he had a little more patience. But I was in the same situation. When you're not getting hits, then you go crazy. You change everything. All of a sudden, you forgot the basics of the game. He's going to play, no matter what. He wishes he can help us offensively, too."