Cornerback Richard Sherman, center, and the Seahawks’ defense led the league in total yards allowed (273.6 per game) and points allowed (14.4 per game). (Jonathan Ferrey/Getty Images)

The Seattle Seahawks will beat the Denver Broncos in Super Bowl XLVIII because a great defense usually beats a great offense. Four Super Bowls matched the top-ranked offense and defense, and three times the defense prevailed — Pittsburgh (1978), San Francisco (1984) and New York Giants (1990). Only San Francisco’s top-rated offense (1989) triumphed.

Just remember that “Iron” Mike Ditka’s 1985 Chicago Bears was the greatest team ever. Offense sells tickets, but defense wins more championships.

Sure, the Broncos scored an NFL-record 606 points this season, but the Seahawks allowed just 231.

The bottom line: Which unit is more likely to be disrupted by the other? Broncos quarterback Peyton Manning is the one that loses this matchup. The Seahawks’ secondary isn’t just cornerback Richard Sherman. This is the finest foursome in years. Manning isn’t going to get anything cheap on them, and he doesn’t have the arm anymore to consistently beat a secondary deep.

The Broncos have five players with 10-plus touchdowns, but receiver Wes Welker is the only real threat. Receiver Eric Decker will be neutralized by this defense. Basically, Seattle has a four-on-two advantage on passing downs.

The Seahawks are ballhawks with a plus-20 turnover differential and 28 interceptions. There’s no way the Broncos repeat scoring six straight series like they did in the AFC championship. It’s going to be a close game, but Seattle can frustrate Manning.

If Seattle’s defense is the difference, is the Seahawks’ offense capable of not losing it? They’re remindful of the Baltimore Ravens team that won Super Bowl XXXV over the Giants. Ravens quarterback Trent Dilfer was largely an average quarterback who delivered a knockout effort while the defense blanked the Giants, who scored only on a kickoff return.

The Seahawks have some offensive playmakers. Running back Marshawn Lynch already has two 100-yard efforts this postseason and four in six career playoff games. Quarterback Russell Wilson benefits more from a great surrounding cast, but he’s certainly talented. Seattle just needs him to not blow it.

One nonfactor will be the outdoor venue, since both teams can play in cold conditions. But Seattle doesn’t have its lunatic “12th man” crowd. It’s very much a neutral site. While Seattle was 6-2 away from home this season, the Seahawks aren’t quite the same team on the road. Meanwhile, the Broncos don’t need to carry the home crowd with them to perform well.

Certainly, the fairy-tale ending would be Manning winning his second title, maybe throwing a late touchdown over that mean-old Sherman, whose only crime was showing America the true emotion of the game after making the final play in the NFC championship.

But Manning will be out of miracles against this defense, which won’t back up in the final minutes.

Prediction: Seahawks 27, Broncos 21