January 3, 2014 at 1:00 am

Chris McCosky

Lions in 2013 were often individually outstanding, collectively baffling

Injuries prevented Calvin Johnson from making another run at a 2,000-yard receiving season. (Daniel Mears / Detroit News)

Allen Park – Sometimes the whole isn’t equal to the sum of its parts, which is another way of saying statistics can lie.

The Lions were 4-2 in the NFC North. They had the third-leading passer (in terms of yards) and the third-leading receiver. They had the sixth-most productive offense, the best third-down defense and the second-best red zone defense.

Yet, when they added up the wins and losses at the end of the year, they were 7-9, out of the playoffs and searching for a new head coach. Jim Schwartz was fired after the team lost six of its last seven games.

“We think we’ve come a long way and Coach Schwartz brought us a long way,” general manager Martin Mayhew said. “But we think it’s time for somebody to take over to put us over the hump and take us to the next step.”

The hump he speaks of is the fourth quarter. The Lions led in the fourth quarter of each of their last six losses. That and a minus-12 turnover ratio will dilute a lot of good deeds over the course of a season.

Here is the final assessment of the Lions’ 2013 season.

Offense

QUARTERBACK: Matthew Stafford has steadily regressed since he threw for more than 5,000 yards and 40 touchdowns in 2011. There are numerous reasons for that. Some it falls on Stafford. His decision-making, his composure and, subsequently, his accuracy fell off noticeably in the second half of the season.

Some of it falls on the team, too. The Lions never addressed the glaring need for a secondary wide receiver to complement Calvin Johnson. When slot receivers Nate Burleson and Ryan Broyles went down with injuries for the second straight season, and Johnson was limited with his own injury issues, Stafford wasn’t afforded a lot of open looks in the passing game.

The most damning evidence against Stafford, though, was his play in the fourth quarter down the stretch this season. His quarterback rating, which overall was 18th in the league, was among the worst (35) in the fourth quarter.

In the final eight games, Stafford completed 54.1 percent with 13 touchdowns and 13 interceptions. Not good enough.

Still, Stafford will be 26 next season, just entering the prime years of his career. A fresh start with a new offensive coordinator could be what he needs to get himself back on track.

Second-half grade: D. Overall grade: C.

RUNNING BACKS: By far the most improved aspect of this team was the run game. With Reggie Bush and Joique Bell providing a complementary blend of speed and power, the Lions finished as the sixth-best rushing team in the league.

Bush became the first Lions 1,000-yard rusher since 2004 and Bell and Bush each had more than 500 yards rushing and receiving – the first pair of running backs to do that in NFL history.

The Lions were able to get some explosive plays on the ground, something they struggled to do the last two years. The only negative was turnovers. Bush lost a career-high five fumbles this season. Bell lost two critical fumbles in the loss to Philadelphia.

Second-half grade: B. Overall grade: B.

TIGHT ENDS / RECEIVERS: It’s hard to characterize the third-leading passing offense as disappointing, but it was. There were too many injuries, too many drops, too many miscommunications, too many botched plays at critical moments.

Johnson was on pace to again make a run at a 2,000-yard season, but nagging pain in his right knee and then his ankle slowed and eventually ended his season essentially two weeks early. He was just a decoy against the Giants and he sat out the finale in Minnesota.

Tight end Brandon Pettigrew, who had an exceptional bounce-back season both receiving and blocking, had his season ended after 15 weeks, too. He had an ankle injury.

After those injuries, plus losing Burleson and Broyles for long stretches, and the early release of Tony Scheffler, the team was left with a group of castoffs – Kris Durham, Kevin Ogletree, Dorin Dickerson, Jeremy Ross.

Second-half grade: C. Overall grade: C.

OFFENSIVE LINE: What was a major concern coming into the season – starting two rookies and a second-year left tackle -- proved to be a strength.

Right guard Larry Warford and right tackle LaAdrian Waddle, both rookies, were solid and unwavering all season. There was a stretch midway through the season when just about every explosive run came through holes created on the right side by these two.

Riley Reiff, after a bit of a slow start, got stronger and more effective with each week, winning more battles at left tackle than he lost.

Anchoring the line were two proud vets, center Dominic Raiola, who in his 13th season had one of his best years, and left guard Rob Sims, who remains as steady as they come.

The run game was better and Stafford was one of the least-sacked quarterbacks in the league. Credit goes to this line and to first year position coach Jeremiah Washburn.

Second-half grade: B. Overall grade: B.

Defense

DEFENSIVE LINE: Being No. 1 in third-down defense, No. 3 in red zone, No. 6 in rush defense speaks to the capabilities of this unit. At times, it was as destructive as advertised. There was a stretch where teams could not run the ball against them, at all – Cowboys, 62 yards; Bears, 38 yards; Steelers, 40 yards; Bucs, 24 yards; Packers, 24 yards.

Then came the Eagles and LeSean McCoy, who gashed them in the snow for 299 yards, most in the second half.

And that speaks to the bewilderment of this unit. At times it was dominant and at other times it was a non-factor.

Clearly, Ndamukong Suh and Nick Fairley have established themselves as an elite defensive tackle tandem. Defensive end Willie Young had a breakout year. Rookie defensive ends Ziggy Ansah and Devin Taylor had flashes of brilliance.

Still, when the numbers were crunched, the Lions ranked 29th in sacks, 23rd against the pass.

Good, not good enough.

Second-half grade: B. Overall grade: C-plus.

LINEBACKERS: DeAndre Levy emerged as a one of the most productive 4-3 outside linebackers in the NFC. His six interceptions were second only to Richard Sherman’s eight. He was stout against the run, too.

His improvement lifted the entire unit. Middle linebacker Stephen Tulloch, playing healthy for the first time in more than a year, again led the team in tackles. There were stretches when he was playing his best football since coming to Detroit.

But 2014 will be his ninth season. He has lost maybe a half-step already and at his size, he cannot afford to lose much more. It’s a worry going forward.

Ashlee Palmer was what the Lions expected him to be – a hard-hitting, run-stopping linebacker. He didn’t play much on passing downs, but he was strong, particularly in short-yardage plays.

The depth was not tested. Only veteran Rocky McIntosh got any significant playing time off the bench. We still don’t know how far Tahir Whitehead and Travis Lewis have progressed in two seasons.

Second-half grade: B. Overall grade: B.

SECONDARY: For every step forward, there was a step and a half back. The Lions ranked 23rd in pass defense and were among the leaders in yielding plays of 40 or more yards.

Chris Houston, though he struggled through perhaps his worst season in Detroit, had two interceptions – the only two by a cornerback.

Had it not been for the steady play of 32-year-old Rashean Mathis, things could have gone completely off the rails.

Bill Bentley, in his second season, survived a slow start and then was injured just as he seemed to be getting comfortable with the nickel position. Rookie Darius Slay showed flashes of being a useful corner, though he too battled injuries.

Glover Quin showed why he was such a priority signing in free agency last offseason. He helped stabilize the back end of the defense, at least as much as one man can.

Louis Delmas showed great courage and toughness, finding a way to play nearly every defensive snap this season. But the knee injuries and the inability to practice during the week took an obvious toll – not just on him but on the overall cohesiveness of the unit.

Second-half grade: C-minus. Overall grade: C.

Special teams

It was like every facet of the team – there were great moments and there were lapses.

The coverage teams were among the best in the NFC for most of the season, but toward the end of the season they would yield a long return at the worst possible time – the 50-yard punt return by the Vikings Marcus Sherels to set up the game-winner, the 56-yard kickoff return by the Giants’ Michael Cox in overtime, just to name two.

Punter Sam Martin validated the Lions’ faith in using a fifth-round pick for him. He was among the league leaders in net punting and he was consistent at dropping punts inside the 20. It’s a shame that his rookie season will probably be remembered more for the botched fake field-goal attempt than his punting prowess.

Kicker David Akers probably won’t get a second season with the Lions. He made 19 of 24 field goals, his last a 53-yarder in Minnesota.

Second-half grade: B-minus. Overall grade: C-plus.

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