The new “Sunday Night Football” makes its debut on NBC this weekend with a stellar matchup — two playoff contenders led by brothers Peyton and Eli Manning. It’s the first time the two have faced each other head-to-head, and there’s much more than pride on the line. Both teams believe they have a shot at reaching the Super Bowl this year, and they’ll get a chance to prove it in prime time.

Earlier on Sunday, the Eric Manginiera begins for the Jets as they travel to Nashville to face the Tennessee Titans. It’s a battle of rebuilding teams, each of whom faces a lot of unanswered questions. Can the Jets rebound in 2006, or is the road back to respectability going to take even longer?

WHEN THE GIANTS HAVE THE BALL

Which Eli Manning will we see? The one with a 14/5 ratio of touchdowns to interceptions in the first half of last season, or the one with the 10/12 ratio in the second half? Scouts say that his mechanics are sound, and that his biggest problem late last year was zeroing in on his primary targets, ignoring the other options and telegraphing his throws. That’s something that he can improve with experience. The Giants will continue to run their balance offense, spreading the ball out to their receivers and pounding the ground with Tiki Barber.

The Colts’ strength defensively is their line. The speed of ends Dwight Freeney and Robert Mathis force teams to make adjustments in their pass coverage. They have to generate pressure because the Colts secondary is vulnerable. Strong safety Bob Sanders is physically aggressive, and one of the few defensive backs in the league who has a chance to contain an elite tight end like Jeremy Shockey. Corner Nick Harper lacks the speed to keep up with receivers like Plaxico Burress, and fellow cornerback Jason David’s lack of size (5-foot-8, 170 pounds) makes him a liability in man coverage.

WHEN THE COLTS HAVE THE BALL

Salary cap pressures forced the Colts to choose between keeping running-back Edgerrin James and wideout Reggie Wayne.They opted for the latter, recognizing that the younger player is on the verge of stardom. Wayne’s toughness makes him a nice complement to the speedier Marvin Harrison, and a great passer like Peyton Manning can get each of them enough catches to merit Pro Bowl consideration.

Dominic Rhodes takes over for James in the backfield, something he did in 2001 when James suffered a knee injury.That year, Rhodes rushed for 1,104 yards and nine touchdowns in just 10 starts, but his own knee injury in 2002 has slowed him.The Colts used their first-round draft pick on Joseph Addai, a running back with an impressive combination of size and speed. Neither has been particularly effective during the preseason.Therefore, look for the Colts to lose much of the balance from their offensive attack and rely more heavily on the passing game.

KEY TO THE GAME

The Giants trio of Michael Strahan, Osi Umenyiora, and LaVar Arrington figures to generate a tremendous amount of pressure against most opposing quarterbacks. If there is any weakness to Peyton Manning, it’s that his footwork gets sloppy when he feels the pass rush closing in. The Giants need to get him off balance and force him to make mistakes.

Lahman’s Pick: Giants 24-17

WHEN THE JETS HAVE THE BALL

The major questions of the preseason remain largely unanswered for the Jets. It’s still unclear whether the rebuilt offensive line is going to give Chad Pennington enough time to throw, and it’s questionable whether the Jets will be able to mount a rushing attack with Curtis Martin sidelined for at least six weeks. The late trade for 49ers halfback Kevan Barlow suggests that head coach Eric Mangini and his staff weren’t enamored with their other options. Derrick Blaylock is a good situational back whose size keeps him from being a full-time player. Second year man Cedric Houston doesn’t have top speed nor does he have the size to run effectively between the tackles. For now, it’s a backfield by committee. Barlow ran for 1,024 yards with the Niners in 2003, and if he can’t regain that form, the Jets are in big trouble.

There are three new starters on the offensive line, including rookies D’Brickashaw Ferguson and Nick Mangold. Most scouts believe that they are capable of becoming stars, but are they ready now? The offensive line surrendered 12 sacks during the preseason on 119 pass plays. That’s an abysmal rate, and no doubt the Titans will test them. They are an extremely aggressive defense, blitzing often and occasionally stacking eight men in the box. They’ll test Nick and Brick early, forcing Pennington to show whether he’s healthy enough to make the quick throws.

WHEN THE TITANS HAVE THE BALL

Billy Volek is the new starting quarterback, though clearly he is just treading water until rookie Vince Young is ready to take over. Coordinator Norm Chow has built on offense based on timing and touch passes, and the Titans’ passing game was largely effective last year. What they struggled to do was run the ball, in part because of a mediocre offensive line. With four of five starters returning, it’s unclear how head coach Jeff Fisher plans to address this weakness. Running backs Travis Henry and Chris Brown both struggled last year, and rookie LenDale White figures to make an impact once he’s healthy. He is listed as questionable for Sunday with an ankle injury.

KEY TO THE GAME

In order for the Jets to make any progress this season, their run defense has to improve dramatically.They finished last season ranked 29th in rushing yards allowed, and the soft play up the middle neutralized the talents of linebacker Jonathon Vilma. The addition of defensive tackle Kimo von Oelhoffen appeared to help during the preseason, but a lot depends on DeWayne Robertson, who has been disappointing in his first three seasons. If Gang Green can’t stop the Titans Sunday, they won’t stop anybody.

Lahman’s Pick: Jets 17–10