Editor's note: This is the second in a series previewing the Pac-12 football season.

LOS ANGELES — Andrew Luck showed up at Pac-12 Media Day with significant facial growth.

"I'm hesitant to call it a beard," he said. "I don't think it's quite there yet."

It's about the only thing the highly touted quarterback has yet to master. Even so, the junior opted to return for one more college season before turning pro.

"I haven't had any regrets. I love being able to represent Stanford University," Luck said. "I'm looking forward to doing that on the field this year. Secondly, I think you can always get better. You can always improve."

However, after guiding the Cardinal to a 12-1 mark as a sophomore, there isn't a lot of room for growth.

That doesn't mean there won't be challenges, though.

Stanford is breaking in a new head coach in David Shaw. The former offensive coordinator was elevated to replace Jim Harbaugh, who accepted the top job with the NFL's San Francisco 49ers.

The transition has been smooth.

"Continuity was definitely something that a lot of the players were hoping for when the coaching change was being made," Luck said. "It's definitely been easier for me."

Shaw noted the differences are minimal. Although his personality differs from that of Harbaugh, the coaches have the same goals and a similar competitive drive.

"We like to teach," Shaw said. "I see myself as a teacher and that's the environment that we've created."

OFFENSE: Luck completed 263-of-372 passes for 3,338 yards and 32 touchdowns in 2010. His top two receivers (Doug Baldwin, Ryan Whalen) have graduated, though, after accounting for 99 receptions. The ground game is solid with all-conference junior Stepfan Taylor returning to the backfield. Tight end Coby Fleener, right guard David DeCastro and left tackle Jonathan Martin are back as starters as well.

DEFENSE: A majority of starters return from a unit that gave up just 226 points over 13 games last season. The Cardinal return their top four tacklers — junior linebackers Shayne Skov (84) and Chase Thomas (70), as well as senior safeties Michael Thomas (61) and Delano Howell (70).

SPECIAL TEAMS: Kickoff return specialist Chris Owasu returned three kickoffs for touchdowns as a sophomore, but was hampered by injuries last season. His return to form will give the Cardinal a valuable weapon and something for opponents to think about.

PLAYMAKERS: Luck finished second to Auburn's Cam Newton for the Heisman Trophy after averaging 291.6 yards of total offense last season. ... Taylor topped 1,000 yards as a sophomore. ... Skov and Thomas made a combined 15 sacks.

TOUGH STRETCH: The last six games will likely tell the story here. A challenging season-ending stretch begins with a home game against Washington and is followed by trips to USC and Oregon State. Then comes a homestand featuring Oregon, California and Notre Dame.

EXTRA POINTS: A favorable road schedule includes just one bowl team from 2010 — Arizona. ... Stanford is coming off a 40-12 win over Virginia Tech in the Orange Bowl. ... Shaw is the first alumnus since Paul Wiggin (1980-83) to serve as head coach of the Cardinal.

Stanford Cardinal

2011 media poll: 2nd, North

2010 record: 12-1, 8-1

Head coach: David Shaw (0-0, first season)

2011 schedule

Sept. 3 SAN JOSE STATE

Sept. 10 at Duke

Sept. 17 at Arizona

Oct. 1 UCLA

Oct. 8 COLORADO

Oct. 15at Washington State

Oct. 22 WASHINGTON

Oct. 29 at USC

Nov. 5 at Oregon State

Nov. 12 OREGON

Nov. 19 CALIFORNIA

Nov. 26 NOTRE DAME

email: dirk@desnews.com