Michael Crabtree’s two seasons at Texas Tech were two of the most impressive that college football has ever seen.

The wide receiver's 231 catches and 46 TDs from 2007 to 2008 are NCAA records for a two-year span, and he became just the seventh player in Big-12 history to crack 3,000 yards receiving in a career with 3,127.

This week, Crabtree will be on the opposite sideline of the quarterback who made those numbers possible: Green Bay backup Graham Harrell.

“That’s my dude, man. I can’t wait to see him,” Crabtree said. “I haven’t seen him in so long. Since the last time we played them [Dec. 5, 2010]. I was watching him in the preseason, he was looking pretty good.”

In the Packers’ final preseason game, Harrell was 13 of 15 for 223 yards and two TDs.

“Me and that dude right there have been through so much,” Crabtree said. “We worked so hard together. It was a pass every down offense and the guy is really smart, you know what I’m saying? He reads the defense so easy.”

Harrell went undrafted out of Texas Tech in 2008 despite finishing his career ranked second in NCAA history with 15,793 passing yards, playing in coach Mike Leach’s Air Raid offense. He was signed by the Packers and spent most of the past two seasons on the team’s practice squad.

The relationships Crabtree built with players and coaches at Texas Tech are still intact, but his ties to the school have started to waver.

“Coach Leach, that’s my coach,” Crabtree said. “Kind of hard for me to pay attention to Texas Tech when my coaches are everywhere else. Leach is at Washington State. [Former offensive coordinator Dana Holgorsen] is at West Virginia and my other offensive coordinator [Ruffin McNeill] is at East Carolina. Half of my coaching staff is at East Carolina or Washington State.”

Leach replaced current 49ers offensive assistant coach Paul Wulff at Washington State and debuted with a 30-6 loss to BYU on Thursday.

Reason to worry?

“Once they get rolling, it’s going to be rolling,” Crabtree said. “They started slow, but they’ll finish fast. They’ll finish better than they’ve been finishing. If it’s not this year, then it’s definitely going to be next year.”

Haggans arrives: Newly signed outside linebacker Clark Haggans will be subjected to a crash course in defensive coordinator Vic Fangio’s defense this week as the team prepares for Green Bay.

“It will be [a challenge], obviously,” Haggans said. “The terminology is different -- a lot of techniques are the same. Been here since Sunday in the classroom with my coaches and coach Vic. Just trying to absorb as much as I can. Just trying to be as spongy as possible and just take it from there.”

There’s also the matter of potential discipline from the NFL due to a DUI arrest in Arizona in 2011.

“Right now I’m just leaving it up to my agent,” Haggans said. “Staying ready. Obviously, I’m going to play some time. Just leaving it up to my agent and see what happens from there.”

It is unclear if Haggans will play will play Sunday.

WR Palmer turned down offers: Undrafted rookie receiver Nathan Palmer elected to stay with the 49ers on the practice squad despite interest from other teams.

Palmer had offers to join New England, Miami and Arizona but decided he was better off staying with San Francisco.

“If I’m going to go somewhere else for the practice squad and get paid the same amount, why start all over?” Palmer said. “I love the Bay Area. I love the fans here. I love the organization. This is the best fit for me.”

Palmer was one of the early bright spots in training camp after a standout career at Northern Illinois, where he caught 93 passes for 1,575 yards and 16 TDs.

Follow 49ers reporter Kyle Bonagura on Twitter: @CBSSportsNFLSF and @KyleBonagura

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