Sunday afternoon at Gillette Stadium the only NFL team with a perfect home record this season will host the most road-tested squad in football.

This divisional round battle pits the Tom Brady-paced Patriots (11-5) against the Philip Rivers-led Chargers (13-4). Los Angeles arrived in New England this Friday fresh off a Wild Card Weekend win in Baltimore, just another in the long list of impressive road victories this season that included success in Kansas City, Pittsburgh and Denver.

The visitors also arrive in Foxborough having to deal with unfamiliar cold weather. Sunday afternoon's weather forecast calls for temperatures in the high 20s with a light wind, though Bill Belichick downplayed any advantage the weather might provide.

"We're playing the Chargers. We're not playing the weather. Whatever it is, it is," Belichick said Friday morning. "We're going to be on the same field."

Though that's true, New England has played in such conditions many times over the years and practiced in cold weather just this week. Meanwhile the Chargers left the 50-60 degree temperatures of Southern California to fly east, and even last weekend's win in Baltimore took place in 50-degree weather.

So while the Patriots won't have to defeat the weather, the Chargers just might. (As such, the scene-setting thermometers were already hung on the exterior wall where the visitors take the field at Gillette in advance L.A.'s arrival late in the week.)

Unlike Belichick, Brady has acknowledged that the environment can be a factor.

"I just think the ability to practice in it like today," Brady said Friday afternoon. "It's very similar to what we're going to get on Sunday so just knowing again, how many layers you've got to put on and how you're going to feel. We didn't have the nice, warm heated benches out there like we will on Sunday. It's cold and that's just part of this time of year. But it's good to be playing when it's cold out. It's good to be playing this time of year in Foxborough. The weather changed a little bit yesterday. It snowed at the start and then got sunny and then got cloudy, then got windy, then got sunny and it's just a bunch of different things. Just to practice in it, we're prepared for it and hopefully we can use some of the things we've learned to our advantage."

Brady also knows, better than anybody, the new level that is postseason football.

"This is the time of year we've got to go out and be at our best. It all comes down to this," Brady said. "It's a production-based league and regardless of what's happened to this point, it's about winning this game."

The rest of his teammates know it too.

"You just keep doing what you've been doing, but it gets to that time of the year where there's no more 'my bads' or 'I'll get that next time.' There is no next time," Devin McCourty added. "It's just the intensity of each play. Each play can change the game. Every guy knows there's no tomorrow and you can just feel that. You feel the energy. Guys are really locked in, ready to go because nothing else matters."

"The playoffs are a whole new season," Rob Gronkowski added. "It's a fresh start. The excitement level from the fans to the players always jumps up another notch, if not a few notches. It's going to be good, it's going to be rocking come Sunday at 1 o'clock and the excitement level from the players to the fans is always up.

As you count down the hours to the rare 1 p.m. Patriots playoff game that kicks off another far-from-rare New England postseason, here are a few keys to the matchup with the well-rounded but soon-to-be-chilly Chargers.

Turn back the clock – The modern NFL is a passing league, right? Brady and Rivers are headed to the Hall of Fame thanks to their right arms. So Sunday afternoon should be a shootout, right? Maybe not. Neither passing attack is the roll-out-of-bed-and-score-30 variety. Both are at their best when they are at the very least balanced. So it's not hard to argue that the rushing attacks – and by extension run defenses – could be the key to this AFC battle. Melvin Gordon was removed from the Chargers injury report after missing practice to knee issues earlier in the week. He's had knee problems dating back to November and hasn't gone for more than 42 yards in a game since then. But L.A. also has Austin Ekeler – who rushed for 554 yards and a 5.2-yard average in the regular season – to turn to against a Patriots run defense that closed the year strong against the Bills and Jets after some ugly work earlier in December. Sony Michel has been hot and cold all year and dealt with his own knee issues. The Patriots offensive line and run game have been much better at Gillette this season, topping 120 yards in seven of eight home games, averaging better than 4 yards a carry in all but one contest. New England probably has to run the ball well against the Chargers No. 9 rush defense to move the ball consistently on Sunday, especially given all the dime packages with six or seven defensive backs that L.A. deploys. The Chargers probably feel they need to do likewise against the Patriots No. 11 rush defense, coming off a very physical battle in Baltimore. Control the trenches, control the ground battle and you make just control the outcome of the game. Yes, this is still 2019.

Seek and destroy – Two of the Chargers best players – Pro Bowl defensive end Melvin Ingram and All-Pro rookie safety Derwin James – are versatile athletes who move around the formation. Ingram can rush from either edge or really seek out a mismatch anywhere along the front. He could be paired up with Joey Bosa to overload one tackle or over David Andrews in the middle. So, locating the Chargers pass rush is step one in trying to deal with it. Similarly in the back end, James can move all over, serving as a weapon in coverage, pass rush or playing the run. Brady obviously has his hands full trying to figure out what LA is doing defensively, both in terms of locating personnel and scheme. Then he has to get to the point where he and his skill position teammates go to work winning play-to-play battles. This game will be both a mental and physical challenge for Brady, Andrews (with his line calls) and the rest of the Patriots offense, especially when it comes to Ingram and James.

Protection plan – The Chargers pass rush is so much more dangerous with Bosa on the field as he's been the second half of the season. The end notched a sack in six of the eight games he's played this fall, including one in last week's win in Baltimore. L.A. had seven sacks against the Ravens, though plenty of that had to do with Lamar Jackson. Still, Trent Brown and Marcus Cannon face a tough challenge against Ingram and Bosa off the edges. The Chargers were just 22nd in sacks per pass play this season, but their personnel is more dangerous than that. And we all know that most of the Patriots past postseason struggles include opponents getting pressure on Brady, who's not always dealt with hits and would-be hits all that well this season. To get to the AFC title game the Patriots need to protect TB12.

Finish the job – Kicking field goals, like L.A. did against the Ravens, can lead to an early postseason exit against a quality opponent. New England should be able to move the ball at times against the Chargers, but it needs to finish off its drives with touchdowns and not field goals. L.A. finished the regular season tied with the Bears for the fifth-best red zone defense in football, allowing touchdowns 50 percent of the time. If they keep to those numbers against New England, keeping the Patriots out of the end zone on half their red zone trips on Sunday, it could be a step toward an upset. The simple things, like third down success, red zone efficiency and turnovers often key the outcomes of games in the postseason. If the Patriots finish drives, they will have a good chance to win. And if they can stop Chargers drives in the red zone, all the better.

Matching up – Stephon Gilmore is the best player in a Patriots secondary that's played quite well over the second half of the season. J.C. Jackson and Jason McCourty are making their postseason debuts, one a rookie and the other an aged veteran. Devin McCourty is coming back from a head injury. The Chargers have a depth of weapons in the passing game led by clear No. 1 target Keenan Allen. All have good size and playmaking ability. Will Gilmore match up with Allen or maybe Mike Williams? Can Jackson and the rest of New England's next-tier coverage options win their battles? Rivers has the ability to spread the ball around to a pretty sound corps of weapons and the New England secondary needs to play the kind of complementary, solid coverage that it displayed down the stretch.

Make a play – Postseason games can make stars or goats. They can extend legacies or cause them to be questioned. Certainly each of these teams has potential playmakers on both sides of the ball, including those that are young and others that are well established. Some will step up on Sunday. Others will come up short. Quite frankly there seem to be a lot of questions (fair or not) about many of New England's most reliable postseason options like Brady, Rob Gronkowski and Julian Edelman. Are they old? Can they still get it done in January? Are their younger counterparts from L.A. more up to the task? Regardless of who it is, some guys are going to have to step up and make big plays on both sides of the ball for New England to win. Maybe that's 12, 87 and 11. Maybe it's Michel, Philip Dorsett and Chris Hogan. But it has to come from somewhere.

Prediction: Anyone who doesn't expect this to be a tight, competitive game might be experiencing some wishful thinking. The Chargers are a good, well-rounded team with the ability to win on the road that's well documented. The Patriots are a good, well-rounded team that's been very, very good at home this season. L.A. did have to travel back and forth across the country over the last week-plus and faces the challenge of the unfamiliar cold weather. In the end, though, this game will come down to the many matchups within it on both sides of the ball. I've said all week that I think the Patriots need to rush for around 150 yards or more to have success on offense. I also think they will need to get a takeaway or two on defense. I think they will do both of those things. Even with all that, there will be a key third down conversion here – maybe to Rob Gronkowski – or a third down stop there – maybe by Trey Flowers – that will be the difference. Put it all together and Belichick, Brady and the home Patriots get the job done for the hard-fought 24-21 victory to advance to the AFC Championship Game for the eight straight year.

What do you think of our keys and prediction? Let us know with a comment below!