Only one Harbaugh — either the Ravens’ John, left, or his brother, Jim, right, the coach of the 49ers will be smiling at the end of Super Bowl XLVII. (John G. Mabanglo/EPA)
When the Ravens have the ball

After eliminating No. 1 overall pick Andrew Luck and the Indianapolis Colts in the first round of the playoffs, the Ravens went on to knock out a pair of future Hall of Fame quarterbacks in subsequent weeks. First, they forced Peyton Manning into three turnovers in beating the Denver Broncos, 38-35, in overtime. In the AFC title game, Baltimore intercepted the Patriots’ Tom Brady twice in a 28-13 victory.

QB Joe Flacco has been nearly flawless in the postseason, throwing eight touchdown passes with no interceptions. Flacco’s passer rating in the playoffs is 27 points higher than it was during the regular season, and his completion percentage has risen in each round.

Flacco has distributed the ball evenly, with touchdown passes to wide receivers Torrey Smith, Anquan Boldin and Jacoby Jones as well as tight end Dennis Pitta. Smith provides a dangerous deep threat. Boldin is dependable over the middle and secures difficult catches with defenders on him.

Running back Ray Rice has 247 yards in the playoffs, including 131 against Denver, which had the NFL’s third-ranked rushing defense during the regular season.

Ravens X-factor: LB Ray Lewis

Ray Lewis is one win from authoring a fairy tale ending to his career, and his teammates no doubt are going to do all they can to make sure the future Hall of Famer goes out with a second Super Bowl ring. Since announcing before the playoffs that he would retire at the end of this season, Lewis has logged a postseason-high 44 tackles. He is the only member left from the Super Bowl XXXV championship team and an inspirational team leader.

When the 49ers have the ball

Colin Kaepernick, a read-option quarterback, provides another set of challenges for Baltimore. Running for 181 yards and two touchdowns in the NFC semifinals, the former backup set an NFL record for most rushing yards by a quarterback in a single game, regular season or playoffs. He added two passing touchdowns to dispatch the Green Bay Packers, 45-31.

Wide receiver Michael Crabtree’s rise has coincided with Kaepernick’s. Crabtree is starting to match the performance expected of the 10th overall selection in the 2009 draft. Over the past five games, he has six touchdowns and three games of at least 107 receiving yards. Crabtree gave the Packers fits with nine receptions for 119 yards and a pair of touchdowns.

Tight end Vernon Davis also is flourishing in the playoffs after gaining just 61 yards on six catches in the final six games of the regular season. The former University of Maryland star has 150 yards and a touchdown on five receptions in the last two games.

Running back Frank Gore provides balance for the league’s top-ranked playoff offense, with a combined 209 rushing yards and three touchdowns.

49ers X-factor: PK David Akers

There’s no telling how fragile Akers’s mental state will be if the 49ers ask him to kick a field goal with the game on the line. Once among the game’s most consistent place kickers, Akers has been undependable and wildly inconsistent since Week 3, missing 15 of 38 attempts, including 5 of 12 over the past five weeks. Akers most recently missed a 38-yard try in the NFC championship game.