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The statistical inputs to the thousands of NFL games simulated are based on rigorous analysis of each team's roster, depth chart and statistically based player ranking. Roster modifications have been made for injuries and suspensions and those players are not part of their team's game simulation.

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Check out our 2011 NFL Season-to-Date page to follow our accuracy week-to-week and find Locks and Upsets of the Week.

Game of the Week: Lions at Cowboys

Two of the top NFC teams are set to tango in Dallas as the surprising 3-0 Detroit Lions take on the 2-1 Dallas Cowboys in the WhatIfSports.com Game of the Week.

Thanks to a revitalized and revamped defense, as well as the return of Mathew Stafford, the Lions have exploded out of the gate. After knocking off a tough Tampa Bay squad in Week 1 and demolishing a crumbling Kansas City team in Week 2, the Lions' sense of hubris may have gotten the better of them in the first half of their matchup with Minnesota, as the underdog Vikings took a 20-0 halftime lead. However, Detroit came storming back in the second half, highlighted by two touchdowns throws from Stafford to favorite target Calvin Johnson. Jason Hanson, who has been with the Lions through thick and (mostly) thin, put four field goals through the uprights, including a 32-yarder in overtime, to give Detroit the hard-earned W over their division foe.

Dallas knows a thing or two about hard-fought wins. After losing a heartbreaker in their season debut to the Jets, the Cowboys found themselves in an early 14-0 deficit in Week 2 against the 49ers. Worse, an injury to starter Tony Romo led to the nine worst words in sports vernacular: "Jon Kitna is beginning to throw on the sidelines." Yet just as Kitna Time tossed his requisite two interceptions, Romo valiantly returned, leading Dallas to 13 unanswered points, including a Dan Bailey 19-yard field goal in overtime, to escape San Francisco with the win. Things were no easier against rival Washington in Week 3, as Romo's struggles with bruised ribs were clearly evident. Alas, thanks to six field goals by Bailey, as well as a bend-but-not-break defensive strategy from coordinator Rob Ryan, the Cowboys eked-out an 18-16 victory.

For the Lions, a vaunted passing attack has masked the severe limitations of their running game. While he's hauled in 15 receptions for 182 yards and a score in the early-going, Jahvid Best has been unable to do much damage in the ground game, with a meager 2.9 average on 49 carries. If Detroit plans on concocting any postseason itinerary, this deficiency will need to be alleviated ASAP. Stafford has been impressive in spreading the pigskin around to Johnson, Best, Nate Burleson and Brandon Pettigrew, but without a dynamic offensive attack, the Lions will be unable to take the next step.

The Cowboys can relate to Detroit's concern. Felix Jones had a breakout game against the Redskins, but the lack of an adequate backup has translated into a measly 78 yards per game in the rushing attack, which ranks 27th in the league. With Romo not at 100 percent, Dallas will need to lean on their backfield for the next few weeks.

So who wins this clash of NFC conference upstarts? According to the WhatIfSports.com award-winning simulation engine, the Lions come out on top 52.3 percent of the time by an average margin of 20-19. Check below for the rest of this week's predictions:

Please note: The 49ers/Eagles, Colts/Buccaneers, Falcons/Seahawks, Saints/Jaguars, Patriots/Raiders, Broncos/Packers, Steelers/Texans, Dolphins/Chargers and Lions/Cowboys games were resimulated on 9/29 to account for injuries and roster updates.

NFL Week 4
Matchup	Win%	Avg Score
Denver Broncos	21.1	17	Boxscore
@ Green Bay Packers	78.9	27	Simulate Game
Carolina Panthers	26.7	15	Boxscore
@ Chicago Bears	73.3	22	Simulate Game
Indianapolis Colts	27.9	16	Boxscore
@ Tampa Bay Buccaneers	72.1	24	Simulate Game
Miami Dolphins	36.1	21	Boxscore
@ San Diego Chargers	63.9	25	Simulate Game
San Francisco 49ers	41.1	18	Boxscore
@ Philadelphia Eagles	58.9	22	Simulate Game
Washington Redskins	50.8	22	Boxscore
@ St. Louis Rams	49.2	21	Simulate Game
Detroit Lions	51.7	19	Boxscore
@ Dallas Cowboys	48.3	18	Simulate Game
New York Jets	55.1	21	Boxscore
@ Baltimore Ravens	44.9	20	Simulate Game
Tennessee Titans	57.4	21	Boxscore
@ Cleveland Browns	42.6	19	Simulate Game
New York Giants	58.8	25	Boxscore
@ Arizona Cardinals	41.2	22	Simulate Game
Minnesota Vikings	62.5	21	Boxscore
@ Kansas City Chiefs	37.5	18	Simulate Game
New England Patriots	62.9	24	Boxscore
@ Oakland Raiders	37.1	20	Simulate Game
Pittsburgh Steelers	65.3	24	Boxscore
@ Houston Texans	34.7	19	Simulate Game
Atlanta Falcons	74.1	26	Boxscore
@ Seattle Seahawks	25.9	18	Simulate Game
Buffalo Bills	74.7	23	Boxscore
@ Cincinnati Bengals	25.3	14	Simulate Game
New Orleans Saints	84.5	28	Boxscore
@ Jacksonville Jaguars	15.5	14	Simulate Game

Joel Beall is the Assistant Content Manager for WhatIfSports.com. He can be reached at jbeall@whatifsports.com.

Jake Westrich is the Digital Content Coordinator for WhatIfSports.com.