ALLEN PARK — The Detroit Lions have plenty of cornerbacks with limited experience. It’s an issue as training camp starts and coach Jim Caldwell doesn’t tip-toe around it.

He’s got veteran Rashean Mathis, 33, who started 13 games for the Lions last season along with Cassius Vaughn, who is 26 and started four games for the Indianapolis Colts in 2013.

Most of the others are untested youngsters including Darius Slay who could be a starter along with Mathis.

“The young boy, Darius Slay, in his second year is taking big steps to become a big-time player in this league,’’ linebacker Stephen Tulloch said on Sunday.

Three corners — Bill Bentley, Jonte Green and Chris Greenwood — were drafted in 2012 and remain short on experience. The Lions also drafted Nevin Lawson in the fourth round.

“We’re young. We have a few guys who have been around the block a little bit, but we’re young,’’ Caldwell said. “But we also have some guys who have talent and ability which we’ve certainly been pleased with. Some of the young guys we were able to bring back last week (when rookies reported early).

“We’ve been looking at those guys closely they’re doing a good job. We have some young veterans who have not played an ordinate amount. We certainly anticipate they’re going to have to step up and play and play well,’’ Caldwell said. “We’re pleased with where we are right now. This is the real test. This is where we’re going to find out what we have.’’

Training camp, which starts on Monday, will offer Caldwell and the coaching staff a better understanding of what they have at the position.

“There are a number of spots — to be honest with you -- there’s a number of spots that we’re going to get a look at them in a totally different arena at this stage,’’ Caldwell said. “We’ll see them under the lights in preseason games, we’ll get an opportunity to see them with pads on. To me those are the things that really matter.’’

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