(SportsNetwork.com) - A lot of writers use the three certainties of life as a literary device when there is a constant in professional sports.
In professional football, there is no better entity to follow death and taxes than the Bill Belichick-Tom Brady New England Patriots.
Like them or not, the Patriots sport the greatest coach-quarterback combination in NFL history and this season, perhaps more than any other, has cemented that fact.
Long a model of consistency, New England is very banged-up these days, especially on defense.
Already without starting defensive tackles Vince Wilfork (Achilles) and Tommy Kelly (knee) as well as middle linebacker Jerod Mayo (shoulder), fellow 'backer Brandon Spikes was the latest addition to that list when he was placed on injured reserve earlier this month due to both disciplinary problems and a knee injury.
The offense, meanwhile, is without star tight end Rob Gronkowski (torn right ACL/MCL), offensive tackle Sebastian Vollmer (leg), and, of course, tight end Aaron Hernandez, who was lost to major legal problems before the season even began.
Through it all, though, Belichick has been able to cobble together another double-digit win season - New England's 11th straight, joining the 1983-1998 San Francisco 49ers as the only teams in NFL history to accomplish that feat - an almost incomprehensible level of consistency in an era of significant player movement from year to year.
Meanwhile, Belichick won his 19th career postseason game against Indianapolis last week to get to the AFC Championship Game in Denver, and he is now just one win shy of Tom Landry for the most ever.
"This is (Belichick's) 14th season with us, but I really think this might be his most outstanding coaching job," Pats owner Robert Kraft told WEPN-FM Radio in New York. "The way these guys have stepped up, 'next man up' so to speak, has just been unbelievable."
That cliched next-man-up philosophy other coaches pay lip service to but rarely embrace is very real with the Patriots.
Up front on defense, Belichick has been making due with waiver-wire pickup Chris Jones and undrafted college free agent Joe Vellano. At linebacker, another waiver acquisition, Chris White, has teamed with rookie second- round pick Jamie Collins and former college free agent Dane Fletcher to help get New England to the conference title tilt.
"Everybody has to step up," Fletcher said. "Everybody's role kind of increases.
"This team we have now reminds me of our 2001 team," Kraft said. "It wasn't the biggest names or collection of stars. It was a team that had a certain mental toughness and truly played together as a team."
Of course, having Brady's steady hand at the controls also helps.
When the Pats hit the field in Denver on Sunday, they will be playing in their eighth AFC Championship Game in 12 full seasons with Brady as a starter (not including 2008 when he was limited to just one game due to injury).
"Tom Terrific" is 18-7 overall in the postseason, the most playoff wins by a signal caller, along with three Super Bowl crowns.
"You need someone with good judgment in that position who also understands how to manage the clock, what's going on and how to adapt," Kraft said when discussing his future Hall of Fame QB. "So we're lucky to have that position filled at such a high level."
That said, if you are putting together a list of reasons why the Pats reached another conference championship, for the first time since 2001 it probably wouldn't start with Brady.
"I think this year the sense of team and putting team first is at the highest level," Kraft said. "We've learned it's not the teams that have the best collection of talent, but it's the teams that really come together, especially in December and January."
That thesis will be tested on Sunday against Peyton Manning and the best offense in the history of football.
Whenever Brady and Manning get together, the narrative centers on them because each has enjoyed almost stunning efficiency throughout their respective careers.
When they last met in the regular season, it was the first time in NFL history in which both signal callers were at least 90 games over .500 as starters. Brady currently has the best winning percentage in the modern era and is at plus-105 for his career (148-43) while Manning is third overall in winning percentage and plus-94 (167-73).
"It's always a great matchup," Broncos defensive coordinator Jack Del Rio, who is 0-7 while coaching against Brady in his career, said when talking about the two QBs. "You're talking about two of the premier quarterbacks in the league."
Some call Manning the best regular-season QB of all-time but hold his pedestrian postseason record (10-11) against him in any "greatest ever" discussions. Conversely, Brady's playoff success is often cited by observers who think he belongs at the top of the heap.
Brady has generally had the edge in the personal rivalry historically, going 10-4 against Manning's Colts and now Broncos, including a triumph earlier this season when Denver jumped out to a 24-0 halftime lead before New England stormed back for a 34-31 overtime win in Foxborough.
Sunday's contest also will mark the fourth postseason meeting between the two superstars and the third AFC Championship Game matchup in the last 11 years, dating back to the 2003 AFC title tilt when Brady and Co. got the best of Manning's Colts, 24-14, at Gillette Stadium.
A year later, Brady was at it again as New England downed the Colts, 20-3, in the divisional round in Foxborough before Manning and Indianapolis got a little revenge in the 2006 AFC Championship Game, earning a 38-34 comeback win in the Hoosier State.
The reality, of course, is Brady and Manning are not competing against each other and will be facing defenses with plenty of issues.
"It's the Broncos versus the Patriots," said Manning when talking about the latest installment of the rivalry. "Certainly Tom and I have played against each other a lot. But when you get to the AFC Championship Game, it's about two good teams that have been through a lot to get there."
The Patriots certainly went through their fair share, but it's hardly a surprise where they ended up.
"I'm sure every team has probably at this point overcome a lot," Brady said. "We're challenged here on a daily basis by coach Belichick to show up, do the right thing, always put the team first and I think that's what this team has always been about."