Shutdown Countdown: This is the San Francisco 49ers' year

Shutdown Corner is previewing all 32 teams as we get ready for the NFL season, counting down the teams one per day in reverse order of our initial 2014 power rankings. No. 1 will be revealed Aug. 2, the day before the preseason begins with the Hall of Fame Game in Canton, Ohio.

No NFL team has been better over the last three seasons combined than the San Francisco 49ers, but they have no Lombardi Trophy to show for it.

There was an overtime loss in the NFC championship game to the Giants, a failed comeback and a fourth-down incompletion in the Super Bowl against Baltimore and a last-minute interception in last year's NFC title game to the Seahawks. As Bill Simmons at Grantland.com wrote in January, no team has ever experienced heartbreaking losses three seasons in a row after reaching the NFL's final four like the 49ers have.

That should change this year.

San Francisco still has the same deep roster, same great coaching staff, same toughness on both sides of the ball. And last year, they were the best team in football by the end of the season.

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I'm not trying to confiscate the Seahawks' rings by saying that. They earned the championship. That's because the NFL's regular season matters, in a real way unlike the tired argument that college football's regular season is sooooo important, considering we've seen teams go undefeated in that sport and never get to play for the title and politics determine who plays for college's championship anyway. Seattle handled business, earned home-field advantage, and that was a major reason they held on and won in the NFC championship game. They deserved the championship. That doesn't mean the 49ers wouldn't have won that game on a neutral field, however.

The 49ers started 1-2, with two blowout losses, and then rolled. In their final 16 games including playoffs. they lost three times. They lost 10-9 to Carolina, who was NFC South champions. They lost 23-20 at New Orleans, where the Saints went undefeated last season, and San Francisco would have won if it weren't for a bad call on Ahmad Brooks. Then the 49ers lost 23-17 at Seattle in one of the tightest games you'll ever watch. They were simply a fantastic football team from Sept. 26 on, and that should carry over.

There are arguments against the 49ers this season. Their secondary is a bit shaky. Losing inside linebacker NaVorro Bowman to a knee injury until at least midseason is a huge blow. Outside linebacker Aldon Smith might get suspended for a while. Maybe all the extra games the past three seasons has a cumulative toll on the veterans.

I still believe in the 49ers. San Francisco is 36-11-1 the past three regular seasons, a remarkable run of success. The championship window might start to close a bit more after this season, and might get really tight if coach Jim Harbaugh leaves. It would be a curious footnote to NFL history if the dominant Harbaugh 49ers never won a championship. I don't think that will be their ultimate legacy.

2013 review in less than 25 words: San Francisco finished 12-4 with a trip to the NFC title game, a successful season for most teams but not the 49ers.

Is the roster better, worse or about the same?: It's about the same. The 49ers lost cornerbacks Tarell Brown and Carlos Rogers and safety Donte Whitner. Former Colt Antoine Bethea can adequately replace Whitner, and Chris Cook can help at corner if he stays healthy or plays up to his former second-round status, which he never did in his four Vikings seasons. Getting receiver Stevie Johnson from the Bills helps, and the draft was pretty strong. The secondary took a step back this offseason, but other good players were added ... let's call it a draw.

Best offseason acquisition: Jimmie Ward could be a big piece for the defense. He was the 49ers' first-round pick from Northern Illinois, a versatile defensive back who is a natural playmaker. He can play safety for the 49ers but it appears the team likes him best right away as a slot cornerback. Maybe he can be a moveable chess piece for defensive coordinator Vic Fangio like Tyrann Mathieu was in Arizona last year. If Ward can come anywhere close to Mathieu's rookie production, the 49ers will have a very valuable player for the defense.

Achilles heel: The 49ers' defense isn't great on the perimeter. The outside cornerbacks are Tramaine Brock and Chris Culliver, with Cook and Perrish Cox as the likely backups. That group won't excite anyone, and on paper it's the weakest part of a very good defense. An injury or two at cornerback and the 49ers might really be in trouble.

Position in flux: One of these years, Frank Gore is going to slow down. It seems like we've been predicting that for about five years, so who knows when it might actually happen. Gore is 31, has 2,187 career carries and did see his average dip from 4.7 to 4.1 last year. He'll hit the wall at some point. The question is, what happens then? Carlos Hyde is just a rookie, albeit a talented one, we haven't seen Marcus Lattimore in game action since his horrific injury at South Carolina, Kendall Hunter tore his ACL and is done for the year and LaMichael James has an elbow injury although the 49ers are hopeful he'll be back for the season opener. Either way, tailback seems to be a bit in flux in San Francisco, unless Gore just beats the odds again and has another fine season at age 31. 

Ready to break out:

He's not a breakout candidate, but I'm putting Colin Kaepernick here because I think he takes his game to the next level this season. We've seen flashes, but he still needs to put it all together as a passer. He took a big step forward last December. He had a completion percentage above 60 percent, something he hadn't done in any of the first three months of the season. His yards per game went from 185.2 before December to 232 yards per game in December, and threw for seven touchdowns and one interception in the final month. The 49ers, not surprisingly, were 5-0 in December. It's not a coincidence that Michael Crabtree's season debut last year was Dec. 1; go figure that a quarterback got better with his No. 1 receiver back. With Crabtree, Anquan Boldin, Vernon Davis and now Johnson to throw to, this is the year Kaepernick goes from being a very good quarterback to a great one.

Stat fact: Bowman has played four NFL seasons, and he has been a first-team All-Pro pick for the last three of them. That's a Hall of Fame pace. Hopefully his knee injury suffered in the NFC championship game doesn't change his career arc. The hope for Bowman is that he returns sometime about midseason, but nobody knows if he'll be the Bowman of old right away, or if he'll reach that level at all this season. It won't be easy for the 49ers to win a Super Bowl if they're practically losing a perennial All-Pro linebacker.

Schedule degree of difficulty: In the NFC West, it'll be tough to win 12 games or more. Of course the biggest two games are against Seattle, and the NFL blew it scheduling them. The game at San Francisco comes on a short week for Thanksgiving, then the teams play again just two weeks later at Seattle. The 49ers need at least a split if they want to win the NFC West.

Burning question

This team’s best-case scenario for the 2014 season: The 49ers need to take care of business in the regular season before they can start thinking about a Super Bowl. Home-field advantage isn't necessary to win the NFC (consider how close the 49ers came last year having to win three straight road games) but it would make life a lot easier. Especially because that would mean no trip to Seattle in January. Winning the NFC West is the first step toward bigger goals that this team is capable of achieving.

And here’s the nightmare scenario: Anything but a Super Bowl victory. There's nothing left for the Harbaugh 49ers to accomplish. Many teams could feel good about a division title or a playoff berth, almost all of them would feel great with just a trip to the Super Bowl, but that's just not the case for San Francisco. There's really only one positive outcome this season.

The crystal ball says: The 49ers finish the job and will be holding the Lombardi Trophy at the end of the season.

Previous previews:
32. Jacksonville Jaguars
31. Oakland Raiders
30. Washington Redskins
29. Cleveland Browns
28. Minnesota Vikings
27. Buffalo Bills
26. Tennessee Titans
25. Houston Texans
24. Dallas Cowboys
23. New York Jets
22. Atlanta Falcons
21. New York Giants
20. Miami Dolphins
19. Kansas City Chiefs
18. Baltimore Ravens
17. Detroit Lions
16. San Diego Chargers
15. Arizona Cardinals
14. St. Louis Rams
13. Carolina Panthers
12. Tampa Bay Buccaneers
11. Pittsburgh Steelers
10. Cincinnati Bengals
9. Green Bay Packers
8. Indianapolis Colts
7. Chicago Bears
6. Philadelphia Eagles
5. New Orleans Saints
4. New England Patriots
3. Denver Broncos
2. Seattle Seahawks

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Frank Schwab is the editor of Shutdown Corner on Yahoo Sports. Have a tip? Email him at shutdowncorner@yahoo.com or follow him on Twitter! Follow @YahooSchwab