Singletary said he saw all he needed to see. He was willing to cut the conditioning exercise short on Friday. Then, Vernon Davis said, "No, we're going to finish this."

Davis, Frank Gore, Shaun Hill and Alex Smith are some of the individuals Singletary singled out as the leaders on the team "leading the pack" during the grueling workouts. Davis, entering his four NFL season, said he is feeling more comfortable in that role.

"I definitely feel like a leader," he said. "I'm more, lead-by-example with what I do with my teammates, doing what the coaches tell me to do and coming to work everyday."

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The 49ers should be in good physical (with an F?) condition this offseason. The Yorks have replaced most of the weights, racks and machines in the weight room. Singletary got his wish of a new steep-rising hill for conditioning at the north end of the team's practice fields in Santa Clara.

Does the hill have a name? "Pain," Singletary answered.

This just in: It took about 2,500 tons of dirt to create the hill. It includes a rise of about 15 feet with a 30-degree slope that's about 45 feet long on one side and a 40-degree slope on the other side.

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The 49ers became a lot more basic on defense after coach Mike Nolan was fired at midseason. With defensive coordinator Greg Manusky gaining autonomy, the defense ditched the "hybrid 3-4 defense" and went solely with a 3-4.

The simplicity has carried over to this offseason.

"We know exactly what we run," 49ers defensive end Justin Smith said. "We have some new twists and wrinkles it in but we're not straying away from what we do well. I think that's important. We're going to run what we run and do it well. I expect us to be a lot better out of the gate and continue from there.

"(We're) sticking purely to a 3-4, and not necessarily having to throw in a bunch of trick-'em stuff."

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Singletary said he has informed Jonas Jennings that the club is going "forward with what we have." He said, "At the appropriate time, we'll do what we have to do." Club sources have told The Press Democrat that Jennings does not figure into the team's plans. He was not invited to the team's voluntary minicamp.

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Cornerback Walt Harris (player rep) and linebacker Takeo Spikes (alternate player rep) are here today after missing Friday's practice. They were attending the union meeting in Maui. But it wasn't just fun and sun, Spikes said. They were tied up in meetings from 7 a.m. to 4:30 p.m., and when they got outside it was raining.

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Singletary declined to provide details on injuries that are keeping players out of practice. DBs Tarell Brown, Michael Lewis and Shawntae Spencer, DL Ray McDonald, TE Delanie Walker and WR Arnaz Battle did not participate Friday. Spencer sustained a torn ACL last season. McDonald underwent offseason surgery on his right knee, and might be brought along slowly in training camp. Walker had some cartilage cleaned out of his right shoulder.

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Receiver Josh Morgan could be in line to be the No. 1 receiver this season - whether or not Isaac Bruce returns for a 16^th NFL season. When asked if he is ready for such a role, Morgan replied, "Yes, sir."

Morgan is still working his way through a groin strain that limited him throughout his rookie season, he said.

Morgan spoke highly of 49ers newcomer Jimmy Williams, calling him "the best corner I've ever played against." Morgan and Williams were teammates at Virginia Tech. Williams flamed out with the Falcons and now finds himself trying to rebuild his career with the 49ers as a strong safety.

Morgan said he is not worried about learning Jimmy Raye's system. "People said Mike Martz had the hardest playbook in the league. If I can learn that (as a rookie), I can learn anything."

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