Every play for the Dallas Cowboys seemed like a struggle. Getting positive yardage required a huge effort or inspired play.

In a conference championship round filled with star quarterbacks, the San Francisco 49ers' defense might end up being the star of the NFL's final four.

San Francisco's defense kept the team in the game until the offense got something going. The 49ers took a lead with Christian McCaffrey's 2-yard touchdown run to start the fourth quarter and then went on a long, grinding drive for a field goal with less than three minutes left. The 49ers defense, which was the best in the NFL all season and dominant on Sunday, wasn't going to give up a score after that.

San Francisco advanced with a tough 19-12 divisional round win at home. The 49ers will face the Philadelphia Eagles next Sunday in the NFC championship game on the road.

With the game on the line, trailing 19-12 with only a few minutes left on the clock, Dallas got nothing against the 49ers. Dak Prescott threw incomplete twice and was sacked on third down, and the Cowboys punted. The sequence highlighted how dominant the 49ers have been all season.

The final four of the NFL includes Patrick Mahomes and Jalen Hurts, who will likely finish 1-2 in the MVP race, and Joe Burrow, who has taken his place among the top five quarterbacks in the league. Then there's 49ers rookie quarterback Brock Purdy, who has done his job, but the 49ers are built in a different way than most contenders. They have a phenomenal defense that can carry the Niners to a win, like it did against Dallas, and a lot of talent on offense around Purdy.

The defensive effort Sunday was enough to lift the 49ers to the championship round. There's no mystery why 49ers defensive coordinator DeMeco Ryans is getting head coaching interviews.

Defenses set the tone

Early on, the defenses let it be known there wouldn't be many points. Every first down was a struggle. Getting in the end zone would be rare.

The Cowboys probably would have led at halftime if not for Prescott's interceptions and Brett Maher's struggles. Prescott threw two costly interceptions. One came in the first quarter in Dallas territory and led directly to a 49ers field goal. The other came late in the second quarter with the Cowboys in field-goal range (though, with Maher's yips, the Cowboys might not have tried one no matter how close they got). Prescott didn't see defensive back Jimmie Ward in coverage, and Ward tipped Prescott's pass up and linebacker Fred Warner picked it off.

That interception came in the final two minutes of the first half, and the 49ers drove down to get Robbie Gould a shot at a 50-yard field goal, and he hit it. The 49ers led 9-6.

The Cowboys played well and got the only touchdown before halftime, to tight end Dalton Schultz. Maher's extra point attempt afterward was blocked, a continuation of his slump that included four missed extra points in the wild-card round.

Dallas had played well on defense, moved it a little bit against a fantastic 49ers defense, and still trailed at halftime. It also had a shaky kicker and a quarterback whose interception problems weren't going away. Neither was the 49ers' defense.

Teams trade scores in 2nd half

The Cowboys got a huge break early in the second half. Ray-Ray McCloud fumbled a punt return and Dallas recovered. The Cowboys couldn't get the touchdown, but Maher got a 25-yard field goal to tie the game.

The 49ers finally got in the end zone on the first play of the fourth quarter. A long drive, highlighted by a circus catch from George Kittle for 30 yards, ended with McCaffrey running through the middle of the line untouched for a 2-yard TD.

Maher kicked another field goal, this one from 43 yards out, and San Francisco led 16-12.

The way San Francisco's defense was playing, the 49ers needed one big drive to put away the game. Even a field goal would be huge. San Francisco went on a long drive with a couple third-down conversions from Purdy. With McCaffrey's snaps limited presumably due to a calf issue, Elijah Mitchell had some tough runs. The Cowboys got a third-down stop but Gould hit another field goal. That drive took 7:59 off the clock and limited how much time Dallas would have left. The Cowboys trailed 19-12 with less than three minutes to go.

The drive right after the 49ers took a seven-point lead was a complete dud. Prescott almost threw an interception on first down. He tried Michael Gallup deep on second down and it was knocked away. He was sacked on third down and Dallas punted.

Dallas needed a miracle after that. The 49ers picked up a quick first down on a pass to Kittle. Mitchell got another first down on a run. The 49ers had to punt but it was with less than a minute to go after Dallas had used all its timeouts. The drive didn't go far and the 49ers were moving on.

The 49ers will face an Eagles team that was the best in the NFC all season. San Francisco's defense won't be intimidated.