Grant Cohn: Midterm report card on 49ers, Part I

Dear Jed York,

You may wonder why you didn't receive this midterm report card last week, at the midpoint of the 49ers season.

That report card would have been bleak. Mostly Ds and Fs.

For the fourth year in a row, your season ended before November. This season, the 49ers fell out of contention before they won their second game.

But, they tried so hard despite their shortcomings. They earned an extra week to boost their midseason grades. And they played the Oakland Raiders, grade-boosters deluxe. The Raiders made the 49ers look fantastic last Thursday. Your team may have improved.

Here are the 49ers midseason grades, starting with their offense. Grades for defense, special teams and coaches will arrive Tuesday.

OFFENSIVE LINE: C-MINUS

The tackles are inconsistent. Joe Staley is 34 and showing age. Mike McGlinchey is a rookie who makes rookie mistakes, although he didn't make any the past two games.

The guards are mediocre. Neither Laken Tomlinson nor Mike Person can block a talented interior rusher one on one. And center Weston Richburg is weak. He can't hold his ground against a strong nose tackle.

Individually, the 49ers offensive linemen struggle in pass protection. They have allowed 31 sacks – tied for third most in the NFL. Not good.

But, as a unit, they typically excel at outside-zone run blocking.

The 49ers offense ranks fifth in rushing yards even though starting running back Jerick McKinnon tore his ACL before the season. Most of his replacements have thrived, which speaks well for the offensive linemen.

But, the offensive line must improve during crunch time. The 49ers don't run well while leading in the fourth quarter. That's when they have to run to use up the clock. That's when the opponent expects them to run and sells out to stop it. A team with a dominant offensive line can run even when the opponent knows it's coming. The 49ers don't yet have a dominant O-line.

TIGHT END: A-MINUS

George Kittle is the best player on the offense.

He's a terrific blocker, and ranks second in the NFL in receiving yards per game among tight ends. He averages 76.9.

Kittle is on pace for 1,230 receiving yards, which would be a higher total than any 49ers player has posted since Hall of Famer Terrell Owens gained 1,300 yards through the air in 2002.

But, Kittle has caught just three touchdown passes this season. He needs to become a bigger scoring threat. Former 49ers tight Vernon Davis caught 13 touchdown passes both in 2010 and 2013.

The 49ers also must develop a No. 2 tight end. Garrett Celek hasn't caught a pass since Week 3. He's washed up. His backup, Ross Dwelley, caught an eight-yard pass in the red zone last week against the Raiders. Maybe Dwelley is the future No. 2.

WIDE RECEIVER: F

Head coach Kyle Shanahan is a wide-receiver guru. He played receiver in college, coached receivers as a young man and hand-selected every receiver on the 49ers roster.

Starter Marquise Goodwin averages 38.6 receiving yards per game, which ranks 66th among NFL wide outs. Fellow starter Pierre Garcon averages 35.8 receiving yards per game, which ranks 73rd. The 49ers have two of the least productive starting receivers in the league.

Their No. 3 receiver, Trent Taylor, averages 19.7 receiving yards per game, which ranks 109th in the NFL. Their No. 4 receiver, Dante Pettis, a rookie second-round pick, has just three catches in six games.

The only bright spots among the receivers are Kendrick Bourne and Richie James, who don't play enough. They should play ahead of Taylor, Garcon and Pettis.

RUNNING BACK: B

None of them can replicate what McKinnon would have contributed to the 49ers passing game. Aside from being an outstanding runner, he ran pass routes like a wide receiver before tearing his ACL. Most running backs run routes like running backs, meaning not well.

McKinnon was a rare talent. But, the 49ers still managed to replace his production in the running game. Matt Breida is averaging 5.5 yards per carry - more than McKinnon ever averaged when was with the Minnesota Vikings. And Raheem Mostert averaged a whopping 7.7 yards per carry before breaking his arm against the Raiders.

The 49ers don't miss McKinnon that much.

Kyle Juszczyk is averaging 12.1 yards per reception, a huge number for a fullback. Tom Rathman never averaged more than 11 yards per catch. Juszczyk needs more targets. He should be the 49ers second-leading receiver after Kittle.

QUARTERBACK: D-PLUS

Jimmy Garoppolo gets a C. He threw three interceptions Week 1 against the Minnesota Vikings. Overcorrected the following week against the Detroit Lions, held the ball too long and took six sacks. Seemed afraid to commit turnovers. Still almost threw an interception which would have lost that game, but the pick didn't count. The Lions committed a penalty away from the play. Garoppolo got lucky.

The following week, he overcorrected again. Instead of staying in the pocket and taking more sacks, he scrambled and tried to make a play he never makes. He ran up the sideline, cut back violently toward the middle of the field like a running back, and his knee fell apart.

Garoppolo lasted less than three games. His completion percentage was just 59.6, and his quarterback rating was 90, slightly below the league average of 92. He has thrown eight picks through eight career starts with the 49ers. That's one interception per game. We still don't know how good he is, or if he's as good as we think.

But, we do know about C.J. Beathard. He's bad. He gets an F. His record as a starter is 1-9. He never should start another game in the NFL. He's a third-stringer at best, a one-read quarterback who turns the ball over more than Garoppolo. More than any quarterback should.

The 49ers need a new backup for next season.

And they may have one. That's why this group gets a D-plus and not a D. Nick Mullens was terrific against the Raiders. His debut was one of the best in NFL history by a quarterback. He seemed like a natural leader, unlike Beathard.

Granted, the Raiders weren't trying. Mullens may be a mirage. Still, he should start the rest of the season, so the Niners learn what he can do.

He makes your team watchable, Jed.

Stay tuned for Part II of the 49ers midterm report card. Please sign and return to me forthwith.

Grant Cohn covers the 49ers and Bay Area sports for The Press Democrat and Pressdemocrat.com in Santa Rosa. You can reach him at grantcohn@gmail.com.