The Patriots won’t take the field this weekend, but there’s plenty to be watching for as the NFL playoffs open with a four-game slate of wild-card round action.

Most importantly, the Patriots’ divisional round opponent will be decided at some point this weekend, either by early Saturday night or on Sunday afternoon.

A quick recap of the scenarios:

* (3) Houston vs. (6) Cincinnati, 4:30 p.m., Saturday. This one is simple: if the Texans beat the Bengals, they’ll travel back to Foxborough next week for a rematch of Week 14’s Monday Night Football tilt. If the Bengals win, they will next take on the Broncos.

* (4) Baltimore vs. (5) Indianapolis, 1:00 p.m., Sunday. If Houston loses, the winner of the Ravens-Colts matchup will face the Patriots on Jan. 13. If Houston wins, the Ravens-Colts winner will head to Denver in the divisional round.

With the scenarios in place, here are five things we’ll be watching for in the AFC wild card matchups.

1. Does momentum matter? In talking to the Patriots, it’s become clear that they don’t believe momentum matters entering the playoffs. But it’s hard to ignore the trending direction of each of the four AFC teams that will play this weekend. While Houston and Baltimore have combined for a 2-7 mark down the stretch, the Bengals and Colts come in on hot streaks adding up to 12 wins in their past 14 games combined. Both teams will have to travel this weekend, making the task tougher, but based on how each has played of late, they look like safe bets to make the games interesting.

Who says Pats fans have nothing to watch this weekend? For starters, you can check out Andrew Luck's playoff debut. AP Photo/Rick Osentoski

2. Playoff pressure. A pair of quarterbacks, Houston’s Matt Schaub (age 31) and Indianapolis’ Andrew Luck (23), will make their first career playoff starts this weekend, putting them to a new test. The magnifying glass is held a little closer on quarterbacks during the playoffs, and both have something to prove in their initial starts in the postseason. Some are wondering whether Schaub has what it takes to make big plays when it matters most, while Luck is looking to build off an impressive rookie campaign and lead his team on a new stage. Without a previous sample to judge either off of, each will begin to mold their playoff legacy this weekend.

3. Lewis returns. Ravens middle linebacker Ray Lewis is likely to return from a triceps injury this weekend, and it’s possible that Sunday will be the final time he takes the field, as he announced on Wednesday that he will retire at the end of this season. His return was sure to inject his team with new life prior to the announcement, but the fact that this game could be his last will only further motivate his teammates. The Colts are also playing inspired football for head coach Chuck Pagano, who recently returned to the sidelines after being diagnosed with leukemia earlier this season. Both teams will be charged by emotion on Sunday.

4. Defensive line impact. Each of the four teams in play this weekend has a Pro Bowl defensive lineman (Robert Mathis of the Colts made the game as an outside linebacker, but plays an end of the line alignment, comparable to Rob Ninkovich), putting the pressure on all offensive lines to stand tall in protection. Houston’s J.J. Watt stated his case for Defensive Player of the Year in the NFL, while Cincinnati’s Geno Atkins might be the best player that no one is talking about on a national stage. Mathis and Haloti Ngata, meanwhile, are veterans with proven track records that speak for themselves. Every play starts with sound blocking and protection up front. Keep an eye on these four studs.

5. Containing Johnson. While the Texans slid down the stretch as a team, their star wide receiver, Andre Johnson, proved once again why he’s one of the best players in all of football. Johnson finished with 1,154 receiving yards during his final nine games, and will meet a stingy Bengals secondary that did not allow a single receiver to surpass 100 yards in a game this season. The Bengals defense is vastly underrated and the secondary has a cast of dependable defenders that play well in coordinator Mike Zimmer’s scheme. Defending Johnson is a big chore, but the Bengals have been up to the task consistently in 2012. Something has to give on Saturday.