Peyton Manning is significantly struggling.

The Denver Broncos quarterback had one touchdown and three interceptions in the overtime win over the Browns, giving him seven touchdown passes and 10 interceptions through six games this season.

It was only two seasons ago that Manning totaled 55 touchdowns and 10 interceptions.

Manning’s 10 interceptions are his most in the first six games of a season since he had 14 in his first season, 1998. That is the only other season in which he had more interceptions than touchdown passes through his first six games (he had six touchdown passes in his first six games that season).

The Elias Sports Bureau notes that Manning's minus-three touchdown-interception differential is the second-worst for any quarterback whose team was 6-0 dating to 1950, surpassed only by Jack Kemp's minus-seven for the 1964 Bills.

Manning now has had three interceptions returned for touchdowns, the most he's had in a season since 2010.

Manning was 3-of-12 with a touchdown and an interception on throws 15 or more yards downfield. For the season, he has completed 35 percent of those throws (17-of-49). Last season, he completed those passes at a 49 percent rate.

How bad have the Broncos' offensive issues been?

They went through a stretch of 26 straight drives without a touchdown. Those drives resulted in seven field goals, 12 punts and five Manning interceptions.

They’ve had five offensive touchdowns in the first half of their first six games of the season. Each of the past two seasons, they had an NFL-best 14 such touchdowns.

Manning has been off-target (overthrown or underthrown) on 21 percent of his passes this season (his highest percentage within the last 10 seasons). He was off-target on 14 of 48 (29 percent) on Sunday.

And yet, even with all that, the Broncos are 6-0. The win was the first for Manning in an overtime game since the 2004 season. He has six 6-0 starts, the most of any quarterback.

According to Elias, that minus-three touchdown-interception differential is the second-worst for any quarterback since 1950 who started and won his team's first six games.