''Winning in December is important,'' McCarthy said, ''and winning in December is difficult.''
Actually, a look at recent history shows the first part is not necessarily the case - especially if the ultimate goal is the Super Bowl. The idea that a strong regular-season finish is a prerequisite for an NFL championship turns out to be one of the myths and misconceptions about the last month of the year.
Only once in the last nine years has a team with a better post-Dec. 1 regular-season record than its Super Bowl opponent won the title. And three times in that span, a team with a losing record down the stretch wound up taking home the trophy: Baltimore was 1-4 after Dec. 1, 2012; New Orleans was 2-3 heading into the playoffs three years earlier; Indianapolis was 2-3 three years before that. Each of those champs beat a Super Bowl foe that had a winning record over its final five regular-season games.
There's also a deep assumption that cold-weather teams dominate in the late season and playoffs.
''The weather definitely plays a part in football games late in the year,'' Pro Football Hall of Fame quarterback Warren Moon said. ''I don't think there's a player alive that loves to play in cold weather, but you can get used to it.''
The Vikings chose the north sideline at TFC Bank Stadium - their temporary home while a dome is being built - because they thought it would help during colder games. With the angle of the sun on December afternoons, the south sideline where the visitors stand is usually completely shaded; if the sun is out, the Vikings' sideline gets all of it.
Coach Mike Zimmer said on-field readings from Minnesota's home game against Carolina on Nov. 30 showed a 20-degree difference between the sunny and the shaded sideline.
''The players thanked me for being on that side a couple of times,'' Zimmer said.
While players - or their fans - in spots such as Buffalo or Pittsburgh might hope for an edge down the stretch in this season's tight AFC playoff race, data compiled by STATS also shows that not all teams based in cold-weather cities thrive this time of year.
Sure, over the past 10 seasons, New England is a league-best 42-7 in December, and 14-4 when it's 32 degrees or colder at kickoff (oddly enough, only Houston, at 3-0, has a higher winning percentage).
But Denver is only 8-9 at 32-or-below at kickoff, a .471 winning percentage that's a significant drop from its .609 in all other games over the decade. Another example: The Cleveland Browns haven't been particularly good in any weather the past 10 years, but their winning percentage drops from .349 at 33 degrees or above to .238 when the mercury drops.
''Sometimes if you take a cold-weather team into warm weather late in the year, that can affect them just as much as it does when you take a warm-weather team and put them in cold weather. Now you've been practicing in colder weather and you have to go out and play in warmer weather - and you're not used to that, either,'' said Moon, who played for the CFL's Edmonton Eskimos before moving to the NFL. ''Fatigue sets in. Guys can get a little more tired or dehydrated.''
At the other end of the spectrum, there are teams from warm-weather sites that do just fine in the cold, such as the Miami Dolphins, who in admittedly small sample size have gone 4-3 at 32-or-below since 2004, a .571 winning percentage that dwarfs their 33-and-above mark of .416.
''If guys excel in cold weather, it has to be something they've been coached on or they've been taught to block it out and say, `We're going to play better,'" Redskins receiver Santana Moss said. ''When coach (Joe) Gibbs was here, he always taught us that `Redskins weather' was bad weather - wet, soggy, gloomy, cold. And we actually won games that time of year. We had the same team that didn't even go to the playoffs, but we won games in December.''
AP Pro Football Writer Dave Campbell in Eden Prairie, Minnesota, contributed to this report.
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