Denver Broncos Keep Winning but Need Peyton Manning to Play Much Better

Peyton Manning used to carry his below-average defenses to victory. Now he is the one holding his team back.

The Denver Broncos moved to 5-0 with a 16-10 victory over the Oakland Raiders thanks mostly to another great effort by the defense.

The unit shut down quarterback Derek Carr and company, while a Chris Harris Jr. interception returned 74 yards for a touchdown helped Denver pull away late. Through five weeks, the defense is allowing just 15.8 points per game, which is a big improvement from last year's 22.1 per game that ranked 16th in the NFL.

While the defensive effort is encouraging, the Broncos won't be able to keep winning unless the offense picks up the pace. For the second time this year, they were able to pull out a win without an offensive touchdown, something that's tough to rely on going forward.

A lot of the blame for the struggling attack falls on the offensive line and the run game, which once again fell short Sunday with an average of just 2.4 yards per carry. However, Manning hasn't looked anything like himself through the first third of the season.

The quarterback finished the win over the Raiders with 266 yards on 22-of-35 passing with no touchdowns and two interceptions. His 62.3 quarterback rating represents his third game under 70 in five chances in 2015. This is something we only saw twice last season and not at all in 2013. 

Of course, the struggles went beyond just the box score.

Denver failed to get into the end zone in any of its three red-zone attempts, with the worst trip ending in a Manning interception. The quarterback forced a throw to tight end Owen Daniels, and Charles Woodson was the one who ended up with the ball.

Brad Evans of Yahoo Sports took a shot at the future Hall of Famer:

Even Manning admitted after the game it was a mental mistake:

The 39-year-old veteran hasn't always had a strong arm, but his strength throughout his career has been his intelligence. When he starts making bad decisions on top of poor throws, there is a serious problem.

Meanwhile, the lack of arm strength remains a major concern. This was seen on Woodson's second interception, although it did come on an incredibly athletic play, especially for a 39-year-old player:

The problem is Woodson never would have been able to make a play if the ball had gotten to Demaryius Thomas sooner. The pass was on target, but Woodson had more than enough time to read the play, cover almost half the field and jump the route.

Bleacher Report's Cian Fahey discussed the arm strength issue:

"

There's your play to point out Manning's dead arm. That ball hung forever.

— Cian Fahey (@Cianaf) October 11, 2015"

Beyond the turnovers, Denver's offense was limited due to poor play on third downs. The squad only converted two of 13 attempts against Oakland, dropping the season average to 35.3 percent. In the previous three seasons with Manning at the helm, the offense never fell below 44 percent and always ranked in the top 10 in the league.

The missed opportunities have led to stalled drives and few points from the offense.

Although no one is legitimately suggesting Manning should be benched, the fact is the quarterback needs to step up his play if the team wants to keep winning during the regular season and in the playoffs. His current pace (3,948.8 passing yards, 19.2 touchdowns, 22.4 interceptions) would equal the worst season of his professional career and be well below what is expected from a quarterback on a contending team.

Head coach Gary Kubiak admitted after the game that things must change on that side of the ball:

With DeMarcus Ware suffering a back injury in the win, the offense could be under even more pressure going forward.

A 5-0 start is obviously nothing to scoff at, as it gives the team a good chance of making the playoffs regardless of what happens the rest of the year. With the AFC West struggling immensely behind them, the Broncos should once again be able to easily pull away for a division title.

However, getting to the postseason is nothing new. The franchise has reached at least the divisional round of the playoffs in each of the last four years. Everyone involved with the organization wants and expects a Super Bowl and won't accept anything less.

The defense has the talent to do its job, but Manning will have to step up his play in order to reach this level.

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