The road back to the Super Bowl became tougher for the Baltimore Ravens after finding out they have to open 2013 on the road -- and it couldn't happen in a tougher place.

Because the Baltimore Orioles wouldn't move a Thursday night game to the afternoon on Sept. 5, the Ravens have to open the season in Denver instead of possibly hosting the New England Patriots. The NFL usually slates the Super Bowl champion at home on Wednesday or Thursday night to open the season.

Instead of hosting the Patriots in one of the toughest venues for opposing teams, the Ravens have to face Peyton Manning on the road with as many as six new starters on defense.

Overall, the NFL has a great schedule in 2013. New rivalries have emerged. Old rivalries remain. Seven of the 11 playoff matchups from the 2012 postseason will be replayed in the 2013 regular season. The schedule features rematches of divisional-round games as well as both conference championships.

Here are the Top 10 matchups to watch this year.

Jim Harbaugh and Pete Carroll have made the NFC West a lot more interesting. AP Photo/Ben Margot

1. San Francisco 49ers vs. Seattle Seahawks, Sunday night, Sept. 15 and Sun., Dec. 8: Four years ago, the only interest in the 49ers and Seahawks was from opponents that wanted their schedule to include those teams. For the networks, this NFC West matchup was a ratings bust. Thanks to coaches Pete Carroll and Jim Harbaugh, the Seahawks and 49ers have developed the fastest, hottest rivalry in the NFL. The competition between the two coaches started in college when Carroll was at USC and Harbaugh was at Stanford. Once Harbaugh stepped onto the sidelines in San Francisco, he turned the 49ers into a Super Bowl-caliber team.

Carroll has revamped Seattle's roster to his standards and has the Seahawks on a similar level. The competition has carried over during the offseason. The 49ers traded for WR Anquan Boldin. The Seahawks countered with a deal for Percy Harvin. The 49ers signed DT Glenn Dorsey. The Seahawks blostered their D-line with Cliff Avril, Michael Bennett and Tony McDaniel. The 49ers signed CB Nnamdi Asomugha. The Seahawks signed Antoine Winfield.

2. Baltimore Ravens vs. Pittsburgh Steelers, Sun., Oct. 20 and Thursday night, Nov. 28: The 49ers-Seahawks rivalry might be trending as the hottest, but Ravens-Steelers remains one of the best in the sport. This AFC North matchup will be different this year, though. Ray Lewis has retired and Ed Reed has moved on to Houston. It will also be different without the presence of James Harrison rushing from the outside linebacker position for the Steelers.

Nevertheless, these teams don't like each other. Even though both have lost key starters because of the salary cap, they remain playoff-caliber teams. They also have great quarterbacks. Joe Flacco cashed in a Super Bowl season for a $20.1 million-a-year contract. Ben Roethlisberger had the Steelers on the path to the playoffs last season before injuries caught up to him and left the Steelers on the outside. Expect two physical games during which both sides are willing to get a few fines to level a few extra hits.

3. Baltimore Ravens at Denver Broncos, Thursday night, Sept. 5: The baseball schedule and a fax machine have made this game even more interesting. The Ravens beat the Broncos in the playoffs last year after WR Jacoby Jones got behind Broncos safety Rahim Moore in the final minute for a 70-yard touchdown pass that sent the game into overtime. The Ravens won 38-35. That play robbed Manning of a chance to go to the AFC title game.

The Broncos get a break by opening the season at home against the Ravens. In fact, the Broncos get a lot of breaks. They have the league's easiest schedule based on 2012 winning percentages, and one of their toughest games is at home to open the season. Another break is playing the Ravens in the first week. Baltimore coach John Harbaugh is breaking in as many as six new starters on a defense that has to contain Manning.

Adding to the drama is the Elvis Dumervil signing in Baltimore. The Broncos tried to cut Dumervil's salary, but once the agreement was reached, Dumervil's camp didn't fax the contract to the league and team in time. He was cut as a result. The Ravens signed Dumervil with the idea of having him and Terrell Suggs as their pass-rushing threats. What a season opener.

4. Denver Broncos at New England Patriots, Sunday night, Nov. 24: When Manning was in Indianapolis, the Manning-Tom Brady game was always one of the main headliners of the season. Manning and Brady may be getting older, but this showdown doesn't get stale. The Patriots are expected to win the AFC East. The Broncos are favored to win the AFC West.

What's great about this year's matchup is that it doesn't appear this is the last chance the two will meet. A year ago, Manning was coming off four neck operations and it wasn't clear whether he could return to the field. Not only did Manning return, but he came away with the AFC's No. 1 seed. John Elway felt good enough about Manning's neck that he locked in two years of guaranteed money for the quarterback at $20 million a year. Brady extended his contract, so the Manning-Brady battles will continue.

Adding to the excitement of this year's game is Wes Welker's move to Denver. The Patriots wanted to drop Welker's salary into the $5 million range despite five seasons in which he caught at least 100 passes. The Broncos had no trouble signing Welker to a $6 million-a-year contract. Welker will be looking to sting his former team. Manning and Brady will continue a classic rivalry.

5. Atlanta Falcons vs. New Orleans Saints, Sun., Sept. 8 and Thursday night, Nov. 21: Even the absence of Saints coach Sean Payton last season because of the bounty suspension didn't diminish the greatness of this NFC South rivalry. The Saints beat the Falcons 31-27 in the Superdome. The Falcons won their home game against New Orleans 23-13. Payton has returned and should be able to return the Saints to the playoffs.

The Falcons finally won their first playoff game in the Mike Smith-Matt Ryan era and want to make this their Super Bowl year. Since 2008, seven of the 10 games between these teams have been decided by eight points or fewer, and these games are sometimes decided by a field goal. The Saints have held the advantage, but the Falcons feel they have the better team. Expect a home-and-home split, but two great games.

6. Atlanta Falcons at San Francisco 49ers, Monday night, Dec. 23: Dealing with a separated shoulder in the final seconds of the NFC title game, Ryan failed to see an open Tony Gonzalez in the end zone and left the Falcons one play away from the Super Bowl. This fall, Ryan gets a chance to finish in this rematch.

It won't be easy. San Francisco's Colin Kaepernick will have more experience and will be more polished at quarterback. The 49ers' defense will still have the confidence of being able to go on the road and win a big game. But the Falcons might be better, too. Gonzalez delayed retirement plans to take one more chance at making the Super Bowl. Steven Jackson has been added to the backfield. The passing game continues to evolve around Ryan.

For Peyton Manning, 2013 includes a meeting with his brother as well as a return to Indianapolis. Jim Rogash/Getty Images

7. Denver Broncos at New York Giants, Sun., Sept. 15: Even though the Brady-Peyton Manning meetings have a chance to continue, this is probably the last time Peyton Manning gets a chance to play against his brother Eli in an NFL regular-season game. Peyton is 37. To meet Eli again, he'd either have to switch teams or wait four more years until the Broncos play the Giants again in the regular season. It's hard to think Manning will play beyond his Broncos contract, which expires in 2016.

Peyton was 2-0 against Eli as the Colts' QB, beating him 26-21 in 2006 in New York and 38-14 in Indianapolis in 2010.

8. Denver Broncos at Indianapolis Colts, Sunday night, Oct. 20: A year ago, the Colts had to tear down the likeness of Peyton Manning from the outside of Lucas Oil Stadium. Knowing they were going to draft Andrew Luck, the Colts let Manning go to Denver. Luck took the Colts to the playoffs as a rookie, but the return of the player who helped build Lucas Oil will be an emotional one. Colts fans idolized Manning, as they should. He won with honor and played with integrity.

Luck has the same characteristics. Owner Jim Irsay asked Luck several times if he would be willing to be the first pick in the draft and play and learn behind Manning. Out of respect for the game and Manning, Luck was willing to do that. Of course, that never happened, but seeing them compete on the same field will be special.

9. Minnesota Vikings at Seattle Seahawks, Sun., Nov. 17: It's fitting the game is in Seattle. Moving vans have been moving parts of the Vikings to Seattle the past couple of years. Former Vikings offensive coordinator Darrell Bevell was the first, accepting the job as Pete Carroll's offensive coordinator in 2011. Also in 2011, the Seahawks signed Vikings wide receiver Sidney Rice and quarterback Tarvaris Jackson.

Jackson was traded after one year, but he isn't missed. As a rookie, Russell Wilson established himself as a playoff-caliber quarterback. Rice remains the Seahawks' No. 1 outside option. This offseason, the Vikings traded Harvin to the Seahawks for a first-round pick this year and a third-rounder next year. This game will be a test to see if the Vikings let too many of their own get away to Seattle.

10. Green Bay Packers vs. Chicago Bears, Monday night, Nov. 4 and Sun., Dec. 29: This great NFC North rivalry needs a reintroduction. When Lovie Smith was first hired by the Bears, he said his main goal was to beat the Packers. New coach Marc Trestman is coming with the same passion. A smart playcaller with a law degree, Trestman speaks softly in a series that is used to bold words.

This series also won't be the same without Brian Urlacher and Charles Woodson. Urlacher was the face of the Bears' defense. Woodson wasn't afraid to call out Bears quarterback Jay Cutler when he struggled. Even though this rivalry has dropped slightly, it's still great because of the fans and because both teams have playoff-caliber talent.