ALLEN PARK, Mich. (AP) Detroit coach Jim Caldwell was asked about positions that are supposed to be particularly tough to learn, like quarterback, tight end and middle linebacker.
Caldwell then started adding some other spots to that category.
''Offensive line, secondary,'' he said.
The context of the question was clear: The Lions drafted Jarrad Davis of Florida in the first round, and general manager Bob Quinn has said he thinks Davis can play middle linebacker. So will learning that spot be an unusually tough challenge for a rookie? Maybe, but Caldwell said it's a process players can handle.
''If an individual has the capacity to learn and learn quickly, he'll be fine no matter where he plays,'' Caldwell said. ''I think middle linebacker is a challenge, just like quarterback's a challenge, like a lot of positions are a challenge. There are none of them that are easy, like I said. So it's going to take some work.''
Caldwell spoke to reporters Friday before practice at rookie minicamp. The Lions had announced the signings of eight draft picks, including Davis , second-round cornerback Teez Tabor of Florida, fourth-round linebacker Jalen Reeves-Maybin of Tennessee, fourth-round tight end Michael Roberts of Toledo, fifth-round cornerback Jamal Agnew of San Diego, sixth-round defensive tackle Jeremiah Ledbetter of Arkansas, sixth-round quarterback Brad Kaaya or Miami and seventh-round defensive end Pat O'Connor of Eastern Michigan.
Wide receiver Kenny Golladay of Northern Illinois, a third-rounder, was the lone Detroit draft pick not among the signees announced by the team, but Caldwell said everyone would be participating Friday.
''When you can get them out there and get them started right on time, it's always good,'' Caldwell said. ''There's a couple different ways that can happen for you, but it worked well for us. There's no delay there just in terms of a guy that's missing for a day or two or longer, so that helps us.''
The Lions mostly took defensive players in the draft and did not address the running back spot. Detroit didn't have a single player reach 400 yards rushing last season, and Ameer Abdullah was limited to 18 carries because of a foot injury.
''I believe Ameer Abdullah, when he's healthy and rolling, he's awfully good. All you have to do is just take a look at the numbers,'' Caldwell said. ''Don't listen to me. Look at the numbers and see when he's on the field for you what he does.''
Caldwell was also asked about the decision, announced earlier this month, to exercise the fifth-year option on tight end Eric Ebron.
''You take a look at it and see his production,'' Caldwell said. ''I can only point to the fact that every single year when you look at his output he's improved. He's gotten better. If he improves at the same rate he's improved the last two years, it's going to be a pretty outstanding season for him.''
NOTES: The Lions announced the signing of 14 undrafted rookie free agents: TEs Brandon Barnes of Alabama State and Robert Tonyan of Indiana State; DEs Alex Barrett of San Diego State and Jeremiah Valoaga of UNLV; WRs Dontez Ford of Pittsburgh, Michael Rector of Stanford and Noel Thomas of Connecticut; RB Tion Green of Cincinnati; DTs Nick James of Mississippi State and Maurice Swain of Auburn; OLs Leo Koloamatangi of Hawaii and Storm Norton of Toledo; and CBs Des Lawrence of North Carolina and Josh Thornton of Southern Utah. ... The team also announced assignments within the scouting department: Kyle O'Brien as vice president of player personnel, Lance Newmark as director of player personnel, Dave Sears as assistant director of college scouting, Steve Neal as area scout, Ron Miles as college scout and Eloy Ledesma as BLESTO scout.
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