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The San Francisco 49ers were two very different teams in 2017. After a nightmarish 0-8 start, general manager John Lynch acquired quarterback Jimmy Garoppolo from the New England Patriots.

A dream run of five straight victories to close the season—including three over playoff teams—followed soon after.

That winning streak lifted Garoppolo's record as an NFL starter to 7-0. It also earned the 26-year-old a jaw-dropping five-year, $137.5 million extension.

Lynch followed up with another aggressive offseason. And that combination of positive vibes has 49ers fans dreaming big as we move into the summer.

The playoffs. Maybe even Atlanta and Super Bowl LIII.

The problem with expectations is this is the time of year they tend to get out of hand. And the ones in Santa Clara, California, need to be dialed back.

Because while we know the 49ers are better—substantially so—we still don't know exactly how good they are.

Rick Scuteri/Associated Press

Garoppolo, who threw for 1,560 yards and seven scores in his first year in the Bay Area, is the centerpiece of all this confidence. As Eric Branch reported for SF Gate, Niners legend Steve Young believes the time served as Tom Brady's understudy in New England uniquely prepared Jimmy G for the hype and expectations he faces:

"Now the expectations are huge, and that's good. He knows how good you have to be. He's watched it—so that's nice. It's not going to be 'Oh, Jimmy, the expectations are too high.' He's like 'No, I know how good you have to be. You can expect me to do whatever you want, but I know how good I have to be. I've witnessed it.' It just makes a huge difference. A lot of players don't have any idea how hard the job is; what really good looks like. And Jimmy's watched it for four years."

Garoppolo played well last year. He took control of the 49ers offense, made plays when he needed to and appeared to mesh seamlessly with head coach Kyle Shanahan. The team made it crystal clear it thinks Garoppolo can lead it to a Super Bowl when it paid him approximately all the money ever.

But we're still talking about a quarterback with seven career starts. A quarterback who averaged an interception a start with the 49ers—the sort of turnover rate that can lead to trouble.

Garoppolo has shown the potential to be great. But he ain't great yet.

San Francisco wasn't any more shy about bolstering the ground game than it was about locking up Garoppolo. After the team signed free agent Jerick McKinnon to a four-year, $30 million contract, Shanahan raved about the versatility the 5'9", 205-pounder brings while speaking with Matt Barrows of the Sacramento Bee.

"Everyone talks about running back and stuff—they need a new position to name people," Shanahan said. "Because he plays running back and receiver and tight end—he does all that. You use him the same way you use all these positions. He's a very good running back. But he also brings a lot of other stuff to the table."

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McKinnon, who set career highs in both rushing (570 yards) and receiving (421) last year with the Minnesota Vikings, is an elusive, versatile back who has become a fantasy football-community darling this year. He's drawn a number of comparisons to Atlanta's Devonta Freeman, another undersized running back (5'8", 206 lbs) who enjoyed great success in Shanahan's offense.

But McKinnon has never gained 1,000 total yards in a season, and in both of the years he topped 150 carries (2016, 2017), he failed to average four yards. He's started just 14 games in four seasons.

Again, we have equal parts potential and inexperience.

San Francisco's most proven wide receiver, Pierre Garcon, has had two 1,000-yard campaigns, but he's recovering from a season-ending neck injury that occurred before Garoppolo took the starting reins. Marquise Goodwin, like Garoppolo and McKinnon, will attempt to build on last year's breakout (56 receptions, 962 yards, two TDs).

And while the arrival of first-round tackle Mike McGlinchey and veteran center Weston Richburg should help fortify the offensive line, it needs it—the 49ers ranked in the league's bottom half in pass protection in 2017, per Football Outsiders.

There are similar defensive questions.

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The Niners D-line is loaded with first-round picks in Arik Armstead, DeForest Buckner and 2017 No. 3 overall selection Solomon Thomas.

But those three first-rounders combined for a whopping 7.5 sacks last year. None had more than three. The 49ers recorded just 30 as a team—26th in the NFL.

San Francisco's most experienced linebacker, Malcolm Smith, missed all of last season with a torn pectoral muscle. Its most talented linebacker, Reuben Foster, makes more headlines off the field than on it. Since January, he's been arrested for both drug possession and domestic violence.

Tony Avelar/Associated Press/Associated Press

San Francisco's secondary features a big name in free-agent arrival Richard Sherman, who headed over after the rival Seattle Seahawks released him in March. Sherman was once one of the NFL's most feared corners, and he wrote for the Players' Tribune he expects to be fully recovered from the Achilles tear that ended his 2017 season by Week 1.

"My rehab has been going phenomenally well, and I think that I'm going to come back better than ever," Sherman wrote. "Realistically, I'm on pace to be back on the field doing drills by June, and there's no doubt that I'll be ready to play come Week 1. That's not even a question."

But Sherman's level of play was down in 2017 relative to his heyday before the 30-year-old's Achilles popped against the Arizona Cardinals. The secondary around him is long on potential but short on experience and production.

San Francisco appears to be better defensively than last year's 24th-ranked unit with Sherman and rookie linebacker (and Foster insurance policy) Fred Warner in the fold. But how much is unclear—and there isn't a big margin for error.

That's because of the division the 49ers play in. The NFC West, top to bottom, is as good as any. After winning the West last year and adding a fistful of big names, the Los Angeles Rams are drawing attention as a Super Bowl front-runner. The Seahawks are the proverbial wounded animal—a perennial contender seemingly on the verge of decline but with a proven superstar quarterback in Russell Wilson.

The Cardinals bring up the rear in most early divisional rankings, and they won eight games last year despite major injuries.

The schedule-makers didn't do the 49ers any favors either. Over the first eight weeks, San Francisco will play all of one team that had a losing record last year.

Ben Margot/Associated Press/Associated Press

That's an October 15, Monday night affair in Titletown against Aaron Rodgers and the Green Bay Packers, who went 7-9. San Fran will open the year against another Super Bowl favorite when it travels to face the Minnesota Vikings on September 9.

Thanks for nothing.

Still, there's considerable reason for optimism in Santa Clara. There's no doubt in his short time running the franchise Lynch has improved the roster—markedly. Shanahan, by all indications, shined in his first year as a head coach. Garoppolo looked the part of a franchise quarterback.

If Garoppolo continues to play at a high level while cutting back on turnovers, McKinnon boosts San Fran's 21st-ranked ground game, Garcon clicks with his "new" quarterback, the front seven improves and Sherman and the secondary hold up, the Niners can hang with the Rams and Seahawks and at least contend for a wild-card spot.

But therein lies the problem. That's a good many questions that have to be answered in the affirmative over a daunting early-season stretch—never mind the three meetings over the last six games with Seattle and L.A.

Seriously, thanks for nothing, schedule gods.

Come up short in just a few areas—in just a few games—and the 49ers could fall off the divisional pace. Garoppolo won't keep winning forever. If the 49ers get off to a slow start, there will be grumbles about a step back.

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There shouldn't be, though. The 49ers are a young team. Lynch's rebuild has gone as well as anyone could dare hope. That doesn't mean it's finished or there aren't areas to improve upon.

No one questions whether the 49ers are better. If the end of last season was any sign, they should be good in 2018—maybe even excellent.

But assigning them greatness based on a small sample size is asking to be disappointed.

Adjust expectations accordingly.

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