Note: This is an opinion piece by MLive.com reporter Nate Atkins

ALLEN PARK -- Detroit Lions coaches have spent all season searching for the running game that their passing attack has never had. The journey hasn't yielded many answers, but along the way, they did find something they could make uniquely theirs.

His name is Jamal Agnew, and he was a speedy but undersized fifth-round rookie cornerback when they approached him during a Week 7 bye and asked if he'd like to try his hand at some offense. Agnew's face lit up like he was back as that kid in San Diego who did everything for his high-school team, including play fullback.

They started with the pitch reverse against the Pittsburgh Steelers, which went for 12 yards around the right end. His sub 4.4-second 40-yard dash speed was a jolt, both to the defense and to an offense that badly needed something beyond the traditional shotgun pass to throw at opponents.

Like any successful offense, the Lions built on that element with deception and versatility. Agnew was a rookie making the jump from a smaller level of college football, and he was still a punt returner and a cornerback living in a 5-foot-10-inch body, so they had to approach it with patience and care. But in time, he began taking reverses and faking them, lining up on the field to alert the defense and even catching a pass in a traditional way.

After his splash debut against the Steelers, Agnew played 3, 2, 4 and 2 snaps in his next four healthy games. Against the Chicago Bears, Agnew became the first Lions player in at least 26 years to record a reception, rush, defensive tackle, special teams tackle, kick return and punt return in a single season.

The very next week, the Lions had a game with their season on the line against the Cincinnati Bengals, and he didn't play at all on offense.

Agnew saw 15 total snaps in Sunday's 26-17 playoff-eliminating loss, but they all came on defense and special teams. A gadget player with two punt return touchdowns of at least 70 yards this season never once touched the ball. Cincinnati wisely kept it away from him on special teams. Detroit stunningly chose to do the same on offense.

I asked Jim Bob Cooter on Thursday what the reason could be for abandoning such a successful wrinkle, but the offensive coordinator avoided any specifics.

"We're aware of what guys have done for us, what guys have contributed for us, and we're going to make the best decision to help win the game as a team," Cooter said.

Cooter didn't feel as if the Agnew package was going to help his offense in a critical game where points were hard to come by. It's a strange approach because when Agnew does have the ball in his hands, what he resembles is a spark. He's averaging 4.5 yards on two handoffs, 9 yards on two receptions and an NFL-best 16 yards on 26 punt returns.

The decision to abandon one of the offense's better talents fit the theme of the day against Cincinnati. The Lions spent three of their first four series running on each of the first two downs with the worst ground game in the NFL. Their hope was to expose Cincinnati's last-ranked rushing defense, but it didn't work, and those short drives ended up exhausting their own defense with a season-high 86 plays.

Perhaps the threat of an Agnew reverse could have helped open up those runs, particualrly on two 4th-and-1 scenarios near midfield when the Lions chose to punt and send that tired defense back on the field. We'll never know because they never tried.

With Detroit now eliminated from the playoffs, this week becomes all about taking an introspective look at the coaching staff and exploring how they develop and deploy the resources they've been given. For much of this season, the use of Agnew has been one of their biggest selling points. They took an undersized rookie cornerback from a small school and turned him into something few could see coming. They built it week by week to where each game opened a few more possibilities than the one before.

Why they abandoned it in the 15th game remains a mystery. The answer isn't coming publicly, but it'll need to come internally now that that's all this week is about.