Ten days before the Arizona Wildcats opened the 2012 season, Marquis Flowers was a safety.

Sir Thomas Jackson was a walk-on, who - after redshirting the 2011 season - hadn't played a game of college football in his life.

Yet, when the UA hosted Toledo in its season opener, Flowers started at one linebacker spot, and Jackson started at another.

That's not exactly an ideal situation for a coach.

"I don't care what defense you play in, the more you play, the more comfortable you get," defensive coordinator Jeff Casteel said this spring.

In the middle of Flowers and Jackson was Jake Fischer, who entered the Toledo game with 26 games and eight starts to his credit.

But you get the point: Outside of Fischer, last year's linebackers were inexperienced.

This year will be different. Flowers flourished at his new position last year, starting all 13 games and leading the squad in both sacks (5 1/2) and tackles-for-loss (13).

Jackson started 12 of 13 games and had 58 tackles.

Both will be back this year with Fischer and, as Casteel said, should be more comfortable.

Here's our reset of the linebackers:

What the group looked like before spring practice: Vaughn Brinkman, Fr.; Keoni Bush-Loo, So.; Dakota Conwell, So.; C.J. Dozier, So.; Jake Fischer, Sr.; Marquis Flowers, Sr.; Devin Gordon, So.; Hank Hobson, Jr.; Cody Ippolito, So.; Sir Thomas Jackson, So.; Anthony Lopez, So.; Shadow Williams, Fr.

What it looks like now: Brinkman, Bush-Loo, Conwell, Dozier, Fischer, Flowers, Gordon, Hobson, Ippolito, Jackson.

Help on the way: Ryan Dunn, Danville, Calif.; DeAndre Miller, Buckeye; R.J. Morgan, Central Point, Ore.; Derrick Turituri, Central Point, Ore.; Philip Wright, Santa Rosa, Calif.

By the numbers: 119: Fischer led the team last season with 119 total stops, which ranked second-best in the Pac-12.

The lowdown: Williams, a walk-on, left the program this summer after redshirting last season. Lopez moved to safety after spring practice.

Conwell and Dozier both played as true freshmen last season and will be in the mix again this year. Conwell, a Pittsburgh native, had a strong spring and could challenge Jackson for playing time.

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Summer stock

The Star will finish previewing the UA's position groups over the next week. Today, we look at the linebackers.

• Coming Sunday: Running backs

Contact reporter Daniel Berk at dberk@azstarnet.com or 573-4330. On Twitter @DSBerk