In Christian McCaffrey, the 49ers have created a touchdown monster

49ers’ running back scoring at an unprecedented clip for 8-3 49ers

When Christian McCaffrey needed a new helmet Thursday night, cameras caught members of the 49ers’ support staff working on each side of the new shell with screwdrivers while it was still on his head.

“They keep two helmets. I didn’t know that,” McCaffrey said after a 31-13 road win over the Seattle Seahawks. “They were making sure the chin strap fit on the second helmet.”

Voila! McCaffrey had become a social media meme.

“Nice. I’ll have to check it out,” McCaffrey said. “I felt like Frankenstein.”

At the rate McCaffrey is scoring touchdowns for the 49ers, it’s as if he was created in a laboratory by a mad scientist. He got two more against Seattle on runs of 1 and 8 yards, giving him 11 rushing touchdowns and 16 for the season with five more on receptions. That leads the NFL and is a franchise single-season record for a running back, breaking the record of 15 set by Roger Craig in 1985.

There are still six games to play.

Next up on Dec. 3 is a rematch of last season’s 31-7 NFC Championship Game loss to the host Philadelphia Eagles, where the lone 49ers’ score following an elbow injury to Brock Purdy was — you guessed it — a 23-yard run by McCaffrey.

After rushing for 114 yards on 19 carries on Thanksgiving — his first 100-yard game since Week 4 — McCaffrey has a league-leading 939 yards rushing and is on pace for 1,451 yards. Throw in 48 receptions for 389 yards and McCaffrey has 241 touches for 1,328 yards. Since having a record-tying 17-game touchdown streak (including playoffs) broken, McCaffrey has three touchdowns in his last two games.

When the season began, the question was whether McCaffrey could rack up 1,000 yards rushing and receiving in the same season for the second time, with Craig and Marshall Faulk of the Rams the only other backs to achieve 1,000-1,000.

Yet when McCaffrey arrived, he went out of his way to let coach Kyle Shanahan know he wasn’t a gimmick back but a running back, capable of a heavy workload and a lot of carries in an old-school sense.

Shanahan hasn’t been shy about taking advantage, with McCaffrey taking 77 percent of the snaps and getting more than 62 percent of the 49ers’ rushing yards.

But even with the big night against the Seahawks, there was some relief in the form of Deebo Samuel and Elijah Mitchell. As recently as two seasons ago Samuel and Mitchell were the hubs of the 49ers’ offense, but due to injury and McCaffrey’s arrival, their opportunities and production have taken a significant drop.

Samuel had seven receptions for 79 yards and four rushes for 15 more, including a 2-yard touchdown run. Mitchell had seven carries for 39 yards.

With the goal of getting McCaffrey to the finish line — which could mean nine or 10 more games should the 49ers make it to Super Bowl LVIII in Las Vegas — the contributions of Samuel and Mitchell will be crucial.

Given McCaffrey’s nose for the end zone, Shanahan’s fixation with him in the red zone is understandable. Including the playoffs, McCaffrey has been a 49er for 26 games and has scored 29 touchdowns.

Including his time in Carolina, McCaffrey has 50 touchdowns in 65 games, which means he’s scoring 0.77 touchdowns per game, which happens to be a greater rate than all-time touchdown scorer and 49ers Hall of Famer Jerry Rice, who had 0.69 touchdowns per game.

(To put Rice’s 229 career regular-season and playoff touchdowns into context, if McCaffrey were to keep scoring at his present rate this season, he’d have 25 touchdowns. At that point, he would still have to average 17 touchdowns per season over the next 10 years to get to 229).

On McCaffrey’s 8-yard run to give the 49ers a 21-3 lead in the second quarter, he took a toss left from Purdy, was stacked up immediately in the backfield, but somehow picked his way through traffic to score.

“I think any time you run behind this O-line, you have to have a lot of trust and patience,” McCaffrey said. “They did such a great job all day. The tight ends blocked super well, Juice (fullback Kyle Juszczyk) blocks well, and our receivers. You’ve just got to trust it and stay on your landmarks and you never know when the hole can open.”

Purdy gets an up-close view of McCaffrey making yardage when it appears there’s none to be hand.

“Christian makes runs like that all the time,” Purdy said. “On that play, it’s like, all right, we’re going to be down inside the 10. He just keeps going and fighting and driving. I look up to that kind of stuff. He gives us a spark and an energy to the offense when we need it most.”

It was one of those times when Shanahan was already looking down at his call sheet, pondering his next move, only to realize McCaffrey had somehow found his way into the end zone. He squirmed in with no apparent hole on the 1-yard run as well.

“Christian finished all of them there,” Shanahan said. “They didn’t look like calls that should have scored, but he made it come to life.”

Like Frankenstein?