Close to a dozen players sat out Iowa’s public scrimmage at Kinnick Stadium on Saturday, mostly for precautionary reasons.

My guess is the one that Hawkeye fans need to be most concerned about is sophomore Jewel Hampton, who is being counted on to step into the starting running back job.

Bryan Bulaga, who might be the best offensive tackle in the Big Ten, didn’t suit up after “tweaking’’ his knee the day before but he ran a few sprints and seemed OK. Receiver Colin Sandeman said his hamstring injury isn’t a big deal. Tackle Kyle Calloway, who is suspended for the first game anyway, took part in a few drills. Chances are, the other guys who sat out won’t make the two-deeps anyway.

But the absence of Hampton, because of his importance to the Hawkeyes’ fortunes and because this is the second time in about a month that he has injured his right knee, has to be cause for concern.

With Hampton out, former walk-on Paki O’Meara ran with the No. 1 unit and actually looked pretty good. People keep dismissing O’Meara as a legitimate contender for the starting job, assuming that redshirt freshman Jeff Brinson is a better prospect, but O’Meara remains ahead of Brinson on the depth chart and he looked better Saturday.

O’Meara ripped off about a 30-yard run at one point while Brinson’s most impressive moment was a play in which he stayed on his feet following a head-on collision with Adrian Clayborn, then was swallowed up by other defenders for about a 5-yard loss. Bear in mind that O’Meara was running against the No. 2 defense while Brinson was carrying the ball against the No. 1s.

Adam Robinson, a redshirt freshman from Des Moines with decent quickness but not much size, is the only other guy who might be ready for any sort of playing time at this time. I could see him being effective against Northern Iowa and Iowa State, but probably not Penn State or Ohio State.

Incoming freshman Brandon Wegher, who rushed for more than 3,000 yards as a senior in high school last fall, was not in uniform for the scrimmage and another true freshman, Brad Rogers, didn’t look that great in very limited opportunities.

The many former Iowa players going through their first NFL training camps will see a lot of each other in their opening round of preseason games this weekend.

Shonn Greene and Matt Kroul, both with the New York Jets, will make their debut Friday night against the St. Louis Rams and former Hawkeye cornerback Bradley Fletcher.

And Saturday’s Tampa Bay-Tennessee game will match center Rob Bruggeman against defensive tackle Mitch King.

Bruggeman, who signed with Tampa Bay as an undrafted free agent, was not regarded as one of Iowa’s best pro prospects, but he may be a starter in his NFL debut. Veteran centers Jeff Faine and Sean Mahan are battling injuries and Bruggeman has been working with the Bucs’ No. 1 offensive unit in practice, according to the Tampa Tribune.

“I’m just going to try to go out there and learn from everything that’s going on,” Bruggeman told the Tribune. “I’m going to be stepping into my first preseason game in the NFL, so I’m sure I’m going to learn a lot of things real quick when I’m out there. I’m just stepping in here, so I’m trying to learn what’s going on and learn from everybody else.”

Things haven’t been going as well for King, a former Burlington star who also was undrafted. He missed two days of workouts because of an illness about a week ago and is listed on the fourth team on the depth chart for Tennessee, which has 13 defensive linemen in camp.

Here’s the position battle you don’t hear much about in Iowa City … yet: Daniel Murray vs. Trent Mossbrucker for the starting place-kicker job. Our gut feeling is that it’s Murray’s job to lose, but after last season it’s hard to figure what Kirk Ferentz might do with this one.

Mossbrucker was having a record-breaking year as a true freshman. He already had scored more points than any freshman in Iowa history by the time the Hawkeyes faced heavily-favored Penn State in November. Then when the Hawkeyes maneuvered into position for a game-winning field goal in the final seconds of that game, Ferentz sent Murray onto the field to kick the game-winner and become an instant hero.

At that point, Mossbrucker’s season went south. He missed two extra point attempts against Pur-due the following week, then made all seven PAT tries against Minnesota while Murray success-fully handled two field goal attempts. Murray did all the kicking against South Carolina in the Outback Bowl.

On paper, Mossbrucker looks like the better kicker. Murray, a junior from Iowa City, is an over-achiever who did a decent job in part-time duty in 2007 and again last season. But other than those two missed PATs against Purdue, Mossbrucker was extraordinary. He missed only two other kicks all season, going 13 for 15 on field goals.

If Murray gets the job, Ferentz admitted there is a possibility he would redshirt Mossbrucker so that he retains three more years of eligibility. Then again, there’s also the chance that Mossbrucker will transfer if he doesn’t get the job this season.

As we said, it’s a battle you may be hearing a lot more about in the weeks to come.

One of the most intriguing battles for the Hawkeyes in fall camp won’t be for a starting job. It will be the head-to-head duel to see who is the backup quarterback behind Ricky Stanzi.

Redshirt freshmen James Vandenberg and John Wienke are – by all accounts – very comparable in ability, intellect and temperament and also have become good friends. Any time coach Kirk Ferentz or offensive coordinator Ken O’Keefe or Stanzi is asked about the two youngsters, they’re very careful to point out how equal they are.

Based on the little bit we saw in the spring scrimmage, which was closed to the general public, Vandenberg looked a little smoother and a little more accurate throwing the ball. But that was just one day. Whatever happens in workouts the next three weeks will decide this thing.

The Hawkeyes are only carrying three quarterbacks on the roster – a few less than most college teams – but Ferentz said he’s not really concerned about that. It just means those three may get more reps in practice each day.

It no doubt helps that Marvin McNutt, who is battling for a starting receiver job, spent the first two years of his Iowa career at quarterback. He would be available to move back behind center on an emergency basis should there be multiple injuries at QB.