SANTA CLARA – Success in the NFL trenches means getting better leverage than the guy opposite you, which isn't easy when you're long-legged and 6-foot-5 like rookie Kentwan Balmer.
"I'm still learning, man," said Balmer, the 29th overall draft pick. "I definitely have to figure it out, as you can see. And coach (Mike) Nolan, he's helping me understand it. And so are the older guys. And so is coach (Jim) Tomsula. So I'm just trying to work as hard as I can for them."
A case in point came Friday after practice when, instead of hitting the showers, Balmer stayed late to hit the blocking sleds. Nolan joined him, offering tips on how to make the sled seem more like an offensive lineman.
"They try to work for an angle to stretch you here or cut you off there," Nolan said. "So you have to line up on the sled in a way that you can make that adjustment yourself, so that it's real. Otherwise, you practice footwork that's not going to happen."
A backup defensive lineman, Balmer nevertheless saw plenty of action Sunday against New England, playing more than 20 snaps. Like his fellow 49er linemen, however, Balmer had trouble holding his ground as the Patriots controlled the ball for nearly two-thirds of the game. Balmer lined up at left defensive end and nose tackle.
"We rotate a lot," Balmer said. "Coach tries to keep guys fresh. And I understand that I have to play when called upon. And I'm trying to get better and do the best I can."
Exit Westbrook; enter Buckhalter – Philadelphia will be without its top offensive weapon for the second time this year. Running back Brian Westbrook, who has scored six touchdowns, was ruled out Friday with two broken ribs suffered in Sunday's loss to Washington.
With Westbrook out, Correll Buckhalter makes his second start of the season. The eight-year veteran rushed 16 times for 66 yards in a 24-20 loss to Chicago in Week 4. Buckhalter is 15 pounds heavier than Westbrook and two inches taller, but Nolan said the two have similar skills.
"If you have the eyes I have, and you can't tell the numbers sometimes, they look the same," Nolan said.
The 49ers' defense hasn't done so well against backup running backs this year. In Week 3, Detroit's Rudi Johnson ran for 83 yards and averaged 5.9 yards per carry. The next week, New Orleans' Deuce McAllister saw his first significant action of the season and ran for 73 yards and a touchdown.
Last week, New England's Sammy Morris and Kevin Faulk combined for 95 rushing yards and two touchdowns.
The Eagles also are without wide receiver Reggie Brown (groin) but could get wide receiver Kevin Curtis (sports hernia) back for the first time this season. Curtis led the team in receiving last season.
Feeling green – Linebacker Roderick Green practiced sparingly this week because of what the team called a stomach virus. His absence increases the likelihood that Tully Banta-Cain will be active for the second consecutive week.
"He did OK," Nolan said of Banta-Cain. "He did all right. He was active. His special-teams play has stepped up as well, which has helped him because that role is not an every-down role so you need to get more out of it."
Banta-Cain shared a sack against the Patriots and was credited with a quarterback hurry.
Read Matthew Barrows' 49ers blog at www.sacbee.com/ninersblog.
