By Tony Moss, NFL Editor

(Sports Network) - Who are the Indianapolis Colts and Denver Broncos? The NFL world is about to find out, as two of the league's elite teams of the moment battle at Invesco Field at Mile High on Sunday.

Are the undefeated Colts really the Super Bowl contender that some believe them to be, or has their 6-0 start been done with mirrors? Is a run defense that is allowing a league-worst 5.2 yards per carry cause for concern? Have narrow, last-minute victories over the mediocre Jets and Titans exposed Indianapolis' deficiencies?

A matchup against Denver, a well-coached 5-1 club with a powerful running game, should answer many of those questions.

Though on the other side of the field, doubts persist about the Broncos' abilities as well.

Is Denver, which is giving up a league-low 7.3 points per game and has surrendered just two touchdowns in six games, simply feasting on teams with struggling offenses? Will the Broncos, who have yet to score more than 17 points in a game and have a grand total of seven touchdowns in 2006 to date, ever display a dynamic offense to match their stifling defense? Is quarterback Jake Plummer ever going to snap out of his funk?

A crowd of 76,000-plus, one that wishes to see its team maintain its current one-game lead over the San Diego Chargers in the AFC West, will be waiting expectantly to have those interrogatives delivered in a positive way on Sunday.

SERIES HISTORY

Denver holds an 11-4 edge in the all-time regular season series with Indianapolis, including a 33-14 home victory in Week 17 of the 2003 season. The Colts had won the previous meeting played between the clubs in Denver, earning a 23-20 overtime victory there in 2002.

The Colts have won the only two postseason meetings between the teams, routing Denver at the RCA Dome in AFC First-Round Playoff matchups in 2003 (41-10) and 2004 (49-24).

Indianapolis head coach Tony Dungy is 4-3 in his career against the Broncos, including the two playoff wins. Denver's Mike Shanahan is 2-4 all-time against Indianapolis, including the postseason losses, and is 3-4 in his career against Dungy.

COLTS OFFENSE VS. BRONCOS DEFENSE

Colts quarterback Peyton Manning (1620 passing yards, 12 TD, 2 INT) comes off his finest performance of the season to date, which is saying something for a player that already had a 400-yard day on his 2006 resume'. In last week's 36-22 win over the Redskins, Manning completed 25-of-35 passes for 342 yards and four touchdowns without an interception or a sack absorbed, finishing the afternoon with a 140.4 passer rating. The outing allowed the perennial Pro Bowler to assume the lead in NFL passer rating (103.2). Top targets Marvin Harrison (39 receptions, 3 TD) and Reggie Wayne (28 receptions, 2 TD) continue to thrive with Manning as their leader. Harrison had seven catches for 73 yards and two scores last Sunday, while Wayne chipped in with seven grabs, 122 yards, and a TD of his own. Also getting into the act were tight ends Dallas Clark (13 receptions, 3 TD) and Ben Utecht (10 receptions), who combined for six catches and 93 yards. Clark also scored his third touchdown of the season. Manning has been sacked just seven times through Indy's first six games.

The lack of a consistent pass rusher had long been a problem in Denver, but the emergence of rookie Elvis Dumervil may have finally brought an answer for that shortcoming. The fourth-round draft pick out of Louisville increased his team-leading sack total to five last week, bringing down Charlie Frye three times and also recovering a fumble. The five sacks are already more than any Denver player had in all of 2005. Ends Ebenezer Ekuban and Patrick Chukwurah have combined for another five sacks on the year. The secondary has five interceptions to its credit in 2006, including a team-leading three for perennial Pro Bowl cornerback Champ Bailey (31 tackles). Bailey had the team's only INT off Frye last week, and fellow corner Darrent Williams (34 tackles) ranked among Denver leaders in tackles with six. The Broncos rank eighth in NFL passing defense (181.7 yards per game).

Though Manning's presence will ensure (perhaps justifiably) that they'll never get a lion's share of the credit, Indianapolis running backs Joseph Addai (354 rushing yards, 19 receptions, 2 TD) and Dominic Rhodes (299 rushing yards, 3 TD, 11 receptions) have contributed to an attack that quietly ranks a healthy 16th in the league in rushing offense (111.2 yards per game). Addai has been the more productive of the two backs, averaging 5.1 yards per carry and going over 100 total yards on two occasions already this season. Rhodes has been asked to get the tougher yards between the tackles, and is averaging just 3.3 yards on 92 rush attempts in 2006. The duo combined for 111 ground yards on 24 carries against the Redskins last Sunday.

Seeking to prevent their first rushing touchdown of the season will be a Denver run-stopping unit that ranks seventh in the NFL (90.3 yards per game) as Week 8 begins. The assignment-conscious linebacking corps of Al Wilson (43 tackles) in the middle and D.J. Williams (31 tackles) and Ian Gold (39 tackles) on the outside has been rock-solid all season, and tackles Michael Myers (22 tackles, 2 sacks) and Gerard Warren (16 tackles) have been active as well. Warren (sprained right big toe) left the Cleveland game and could be out for Sunday, meaning Demetrin Veal (13 tackles, 1 sack) could be called upon to start. The Broncos held former teammate Reuben Droughns to just 33 yards on 12 carries last week, with his longest run going for seven yards.

BRONCOS OFFENSE VS. COLTS DEFENSE

There have been whispers around Broncos camp that the next two games, against Indianapolis and Pittsburgh, will represent a final audition of sorts for struggling Denver quarterback Jake Plummer (984 passing yards, 4 TD, 7 INT). Plummer carries a weak 60.4 passer rating into Week 8, is averaging a little over one touchdown drive led per game, and is surely operating on borrowed time as it is with first-round phenom Jay Cutler waiting in the wings. If Plummer can't move the team with greater frequency over the next two games, it could become Cutler's show. Looking to be involved in the passing game on Sunday will be wideouts Javon Walker (29 receptions, 2 TD) and Rod Smith (22 receptions, 1 TD), who have been Plummer's only regular targets this season. Walker caught nine balls for 107 yards in Cleveland last week. The Denver line has allowed just nine sacks on the year, though the season-ending knee injury suffered by left tackle Matt Lepsis last week could put the effectiveness of the trench group in peril. Expected to take Lepsis' place is Erik Pears, a first-year player out of Colorado State.

There is at least mild concern in Indianapolis over the work of the Colts' once-vaunted pass rush, which enters Week 8 tied for the third-fewest sacks in the league (10). Part of the problem has been the unavailability of Pro Bowl defensive end Dwight Freeney, who has been limited by buttocks and shoulder injuries and has yet to post his first sack of 2006. Fellow end and running mate Robert Mathis (29 tackles, 4.5 sacks) has held up his end of the bargain, though he too has gone sackless in his last two games. Despite these events, Indianapolis ranks third in NFL passing defense (167.3 yards per game), though the fact that the Colts have faced the second-fewest attempts in the league has something to do with that trend as well. There is a mixed blessing in the secondary, as safety Mike Doss (torn ACL) has been ruled out for the rest of the year on the same week that Bob Sanders (knee) is scheduled to appear for the first time since Week 2. Doss leads the Colts in interceptions with two. At cornerback, Nick Harper (22 tackles, 1 INT) and Jason David (20 tackles, 1 INT) will bear most of the responsibility for slowing Walker and Smith this week.

As always, the number one directive for the Denver offense on Sunday will be to run the football. Despite facing some early questions about the abilities of the ground attack, the Broncos and their zone-blocking scheme are a solid fourth in NFL rushing offense (143.3 yards per game), with Tatum Bell (585 rushing yards, 2 TD, 13 receptions). Bell, who last week posted his third 100- yard game of the season, is averaging a healthy 4.7 yards per carry and appears well on the way to his first 1,000-yard season as a pro. Backfield mate Mike Bell (141 rushing yards, 1 TD) had been used sparingly as Tatum Bell had begun to emerge, but the former Bell did garner 10 carries last week against Cleveland, his most touches since Week 2.

The Colts enter Week 8 ranked a distant 31st in the league against the run (158 yards per game) and last in yards allowed per carry (5.2), though there is reason for optimism on that front. First is the return of Sanders, one of the team's best run-stoppers, and the other is the presence of ex-Buccaneers tackle Anthony McFarland, who made two tackles in his Indianapolis debut last week. McFarland, who was obtained from Tampa Bay at the trade deadline, will this week start in place of the injured Montae Reagor (facial injuries sustained in an auto accident). Seeking to contribute behind the tackles will be linebackers Cato June (61 tackles), Gary Brackett (54 tackles), and Gilbert Gardner (33 tackles), none of whom have made a wealth of big plays this season. Indy did a decent job against the run last week, allowing Washington running backs Clinton Portis and Ladell Betts to compile a modest 95 yards on 22 carries.

OVERALL ANALYSIS

Much will be made of Peyton Manning's recent record against the Denver Broncos, which has included plenty of completions, yards, and wins. But Manning has yet to face this configuration of the Denver defense, which is improved in all phases over the one that the quarterback last saw, and has won games in 2006 due to an almost robotic form of assignment football. Look for the Broncos defense to frustrate the daylights out of Manning for four quarters. On the other side of the ball, Denver will be able to do what it does best - run the football - against an Indianapolis defense that (even with McFarland and Sanders in tow) has giant, exploitable weaknesses.

Sports Network Predicted Outcome: Broncos 27, Colts 13