ALLEN PARK, Mich. -- Some friendships are built to last, seamlessly going from one year to the next, the connection strong, the times fun and bright. Others don’t go quite as well. They are rocky, bumpy, have their issues.

Recently, the pairing of the Detroit Lions and the run game would definitely fit into the latter category. Coach Jim Caldwell referred to the running game as “a quarterback’s best friend” on Tuesday.

The Lions may want to consider improving that friendship.

Detroit’s run game continues to be one of the worst in the NFL -- and is currently worse than in any other season under Caldwell. The fourth-year head coach has said multiple times that he wants his run game to be “respectable” and that 4.0 yards per carry is a good bar to hit.

The Lions have never averaged 4.0 yards per carry or 90 yards per game over a full season in Caldwell’s tenure. They’ve consistently been in the bottom third of the league -- and often worse -- in both yards per game and yards per carry under Caldwell.

This season, though, the Lions have been especially bad running the ball. Detroit is averaging 80.8 rushing yards per game, and if that holds through the rest of the season, it will be the fourth straight season the Lions' run game has declined in yards per game under Caldwell. The 3.35 yards per rush is also down 0.39 yards from last season.

The Lions also haven’t had a 100-yard rusher in a game since 2013, when Reggie Bush had 117 yards on Thanksgiving. Now, headed into this year's Thanksgiving contest, the Lions have gone 62 games without a 100-yard rusher. It’s the longest streak without one by a team in two decades.

Lions players either have chosen not to divulge what the issue is or have been saying it's a little bit of everything.

“It’s not always player issues. It’s sometimes we may not be dialing the right thing at certain times,” running back Ameer Abdullah said. “At the same time, it’s about just bringing a good attitude, bringing an attitude of just executing your job, really. I think that’s really what it comes down to, if you ask me.

“It comes down to guys just saying, ‘Hey, I’m going to be better than the next guy this play.'"

Abdullah, who is Detroit’s leading rusher with 491 yards, also said, “I got to be better. That’s the thing I keep telling myself. Just try to do better. Just keep going hard.”

Abdullah is averaging a career-low 3.41 yards per carry this season on 144 attempts, while Theo Riddick is averaging 3.53 yards per carry on 104 fewer rushes.

Matthew Stafford said he hasn’t thought about what a consistent run game would do for him. Caldwell called Detroit's run game “inconsistent” Tuesday, but when asked why there’s been a consistent disconnect between what he would like out of his running game and what has actually transpired, he didn’t have many answers.

“I think you brought this up, this is probably the fifth time that maybe you’ve brought this particular subject up,” Caldwell said. “The fact of the matter is it is what it is. What I’m more concerned about, and I’ll repeat it over and over again, I want to win however it takes to win, OK. And that’s what counts to me.

“So right now, we’re still not winning as much as I would like to win, and we’ve still got a ways to go, but I think our guys are heading in the right direction.”

Right direction might be a tough description. The Lions have rushed for more than 4.0 yards per carry in just two of 10 games this season, and they’ve been under 3.0 yards per carry in two of the past three games -- wins at Green Bay and Chicago.

The inconsistency has been prevalent throughout Caldwell’s tenure with Detroit. The Lions have cycled through Bush, Joique Bell, Abdullah, Riddick, Zach Zenner, Dwayne Washington and Justin Forsett during Caldwell’s four seasons. They’ve had two different offensive schemes. They’ve had two different offensive coordinators, running backs coaches and offensive line coaches. There have been -- as with almost any team -- multiple combinations of offensive linemen.

The one constant during that is Caldwell, who has not consistently employed a strong running game during his time as a head coach or coordinator in the NFL or at Wake Forest.

Stafford said he wasn’t sure if his job would be easier if the run game was going well, but that “the more balanced we can be, the better.” Detroit has had some games where the run/pass ratio is balanced, but the difference in success between the pass and run has been stark. Stafford said he didn’t think the Lions' scheme -- a large amount of it similar to what Indianapolis ran and with major roots in Tom Moore’s philosophy -- hampered their chances to run the ball.

Instead, Stafford said that sometimes things work out and sometimes they don’t. For the Lions, however, trying to run the ball has not worked out much at all.