SAN JOSE — On the second day, Michael Crabtree rested.
The 49ers' wide receiver attended the morning chalk-talk session at the players-only offensive minicamp Tuesday, but didn't participate in the practice. The reason: Sore feet.
Fellow wideout Josh Morgan, who has worked with Crabtree during the offseason, said the third-year wide receiver had aching feet after wearing new cleats during Monday's minicamp-opening practice on San Jose State's field turf.
Morgan said Crabtree sat out as a precaution. He wasn't sure whether Crabtree would return to practice today.
"He's good," Morgan said. "He doesn't want to get hurt out there. He just wants to learn the offense. So he's good."
Later, Morgan was asked whether "Crabtree's feelings were hurt" — a reference, perhaps, to the negative attention Crabtree has received by not participating with his fellow wide receivers in offseason throwing sessions with quarterback Alex Smith. On Monday, Crabtree made it clear he didn't agree that Smith is the favorite to be San Francisco's starting quarterback.
"Crabtree's all right," Morgan said. "His feelings aren't hurt. Nothing's wrong with him. Just his feet were too sore to come out here. That's all it is."
During the 30 minutes of Tuesday's practice open to the media, rookie quarterback Colin Kaepernick was mostly a spectator as Smith and David Carr threw passes to the running backs, wide receivers and tight ends. Kaepernick is limited after undergoing a minor surgical procedure on his lower left leg in early May.
But Morgan, who has termed himself Smith's assistant coach, said he's keeping Kaepernick's mind busy.
"I mess with him, making him think that I'm a little slow," Morgan said. "I keep asking him (about) a play. He thinks I'm asking because I really don't know, but I'm just doing it to get him used to saying it all the time ...
"He's doing it, but he's kind of looking at me like &‘Why you keep asking me? They said you were one of the smartest ones. Why do you keep asking me for?' So I'm going to keep asking him."
WALKER EXPECTS MORE WORK
Backup tight end Delanie Walker said the first two days of the minicamp have primarily covered just the offensive basics. But he's seen enough to anticipate an expanded offensive role this season.
"I don't want to give it away, but it seems like it's going to be a lot of two tight-ends sets," Walker said. "Just by what we're doing right now. We haven't even opened up the playbook a lot, but it looks like it will be a lot of two tight-end sets. I'm looking forward to it."
Niners coach Jim Harbaugh made extensive use of his tight ends at Stanford last year. The Cardinal's tight ends accounted for 65 catches, 833 yards and 13 touchdowns.
JOHNSON EAGER TO LEARN
During a news conference after the NFL draft, Harbaugh raved about Ronald Johnson's passion and desire. When asked about the rookie wide receiver from USC, Morgan also highlighted Johnson's drive.
"Ronald just wants it so bad," Morgan said. "That's probably the best thing I could say about him. He's so eager to get everything right now. When you're that eager to learn, and that eager to get it in you so you can get out there and play, you're always going to have some positive results."