Beckham has made enough of an impact that Guillen has begun to envision the rookie in the big league picture, a picture he wasn't near when Spring Training began.
It's also a picture that has yet to be fully assembled.
"He's had a great Spring Training and he's making it tougher on us to make that decision," said Guillen of Beckham. "He continues to impress everybody. It seems like he belongs in the big leagues.
"Right now, we have  games left. If he continues to do that, then we have to think about what we're going to do. I'm really, really impressed with him, but in the meanwhile, I think we have more talent behind him that can help us, too."
Hitting coach Greg Walker described Beckham on Sunday morning as a kid he hasn't had to do much with, swing-wise. Beckham is a legitimate No. 1 pick and right where he should be, according to Walker.