SANTA CLARA, Calif. >> When the San Francisco 49ers dealt a bevy of draft picks to Carolina last October for Christian McCaffrey, some skeptics asked whether they overpaid for a running back in a passing league.

Nearly 12 months later, coach Kyle Shanahan can’t even imagine what life would be like without McCaffrey driving the Niners offense.

“No, don’t ever say that,” Shanahan said when asked if he could have imagined not making the deal.

The midseason addition of McCaffrey last year immediately transformed the 49ers from a middling offense into one of the most productive.

Now with an entire offseason to fully integrate McCaffrey into the system, the Niners offense has gone to an even higher level, scoring at least 30 points in the first four games of the season for the first time in franchise history.

McCaffrey is a major reason for the success and is being talked about as being the first non-quarterback to win MVP since Adrian Peterson in 2012. McCaffrey currently is in the top 10 for odds to win the award, according to FanDuel Sportsbook.

“I thought he played like it last year when he was here,” Shanahan said. “Christian’s so awesome, he helps us win every time he’s out there.”

The trade that sent picks in the second, third and fourth rounds of the 2023 draft and a fifth-rounder in 2024 to Carolina to acquire McCaffrey last October has not only transformed the 49ers, it has done the same for McCaffrey.

After becoming the third player ever to gain 1,000 yards rushing and receiving in the same season in 2019, McCaffrey was hampered by injuries in 2020 and ‘21 and had become overlooked playing for the struggling Panthers.

Even his new teammates in San Francisco didn’t realize how good he was.

“I didn’t,” All-Pro left tackle Trent Williams said. “I’m not going to lie. I watched him from afar for a long time. I knew he was really, really good and really special and could do a lot of things conventional running backs can’t do. But watching him play conventional running back, it’s like, ‘Wow.’ How can you be that talented in the open field, playing wide receiver and then lineup in the I-formation and still continue to gash defenses. He’s a special player, he really is.”

McCaffrey has already broken Jerry Rice’s franchise record by scoring a touchdown in 13 straight games in the regular season and playoffs and is off to a historic start this season.

He has 600 yards from scrimmage and seven touchdowns in four games, marks previously reached only by Hall of Famers Jim Brown (1958 and ‘63) and Emmitt Smith (1995).

“He’s just a complete running back,” fullback Kyle Juszczyk said. “I don’t think there’s anything he can’t do. He can run between the tackles, he can run outside, he can run routes, he can pick up blitz protections. He’s just such a complete football player and a guy that you can put anywhere. You can put him at running back, you can put him at receiver and he’s going to go out there and excel.”

McCaffrey has started 17 games since joining the Niners, averaging 120.4 yards from scrimmage in those games with 20 touchdowns as well as an additional one throwing.

Teammate Deebo Samuel called him a “Swiss Army knife” for his versatility and his presence puts a huge stress on defenses who also have to worry about stopping playmakers such as Samuel, receiver Brandon Aiyuk and tight end George Kittle.

They all noticed the difference as soon as he arrived and the field opened up as attention was focused on slowing down McCaffrey.

“I mean right when we got him, I was like, it’s like (the) Madden (video game) for Kyle,” Kittle said. “He can just make up whatever he wants to make up. Who do you want to take away?”

Defenses haven’t taken away much. San Francisco has won 16 of those games that McCaffrey has started, losing only in the NFC title game when they played essentially without a functional quarterback for a long stretch after Brock Purdy injured his elbow and are averaging 29.2 points per game.

“He’s a freak,” Purdy said. He does everything for us. Obviously, he can run the ball, can run routes out of the backfield, can line up as a receiver and run routes. He does everything, man. So, we’re thankful for him.”

NOTES: LB Dre Greenlaw (ankle), CB Charvarius Ward (heel), Elijah Mitchell (knee) and OL Jon Feliciano (concussion) missed practice. … WR Deebo Samuel (knee) and WR Jauan Jennings (shin) were limited.