Instant analysis of 49ers’ 42-10 rout of Dallas Cowboys in Sunday night spolight

SANTA CLARA – Sunday night’s stage offered up the 49ers’ greatest regular-season win in Levi’s Stadium’s 10-year history, a 42-10 thrashing of the forever-rival Dallas Cowboys.

Prisoner of the moment? Perhaps. But this certainly was the 49ers’ most dominant victory in their 5-0 start to this season, and while it came in the NFL’s showcase timeslot, it also attracted franchise legends such as Steve Young, Jerry Rice, Frank Gore, and Bryant Young.

“Let’s go!” tight end George Kittle shouted to the capacity crowd via the stadium’s giant video screens, after scoring one of his career-high three touchdown catches from Brock Purdy’s on-the-mark passes.

Purdy finished with a career-high four touchdown passes, Christian McCaffrey chimed in with his 14th consecutive game with a touchdown (1-yard run), and, in representing the 49ers’ menacing defense, Fred Warner produced a sack, a forced fumble, and an interception.

Not only did the 49ers keep pace with the Philadelphia Eagles (5-0) as the NFL’s only undefeated teams, this marked a 15th consecutive regular-season win. The Cowboys fell to 3-2, nine months after losing here 19-12 in the divisional playoffs.

The 49ers have won 11 straight at home, and after this resounding end to a three-game homestand, they play their next two on the road: Sunday at the Cleveland Browns (2-2; Week 5 bye) and Monday night, Oct. 23 at the Minnesota Vikings (1-4).

Never before have the 49ers enjoyed such a string of success at their $1.2 billion Silicon Valley office. Not counting their 4-0 playoff record here, the 49ers’ other standout wins also came in prime time: a November 2019 rout of the Green Bay Packers to help spur a Super Bowl run, and a 2021 Monday night season saver against the Los Angeles Rams.

These 49ers have scored at least 30 points in all five of their games, and they surpassed the 40-point mark via Kittle’s hat trick, plus a touchdown each from McCaffrey, Kyle Juszczyk (1-yard catch) and Jordan Mason (26-yard run).

Watching from the opposing sideline was quarterback Trey Lance, the 49ers’ 2021 first-round pick who got traded to Dallas six weeks earlier, having lost his starting job to Purdy and the backup role to Sam Darnold.

Cowboys quarterback Dak Prescott got benched (for Cooper Rush) after interceptions on three consecutive possessions — by Warner, Tashaun Gipson Sr. and Oren Burks. The 49ers’ defensive brilliance also was reflected with their most sacks since the season opener, and they had three by halftime, via a combination of Nick Bosa, Arik Armstead, Warner and Dre Greenlaw. Warner also forced a fumble that Kevin Givens recovered.

Of utmost concern to their high-scoring offense: left guard Aaron Banks left with a biceps injury in the third quarter; ruled questionable to return.

The 49ers opened in typical scoring fashion, charging 75 yards down the field before Purdy rolled left and threw a 19-yard strike to an open  Kittle for his first touchdown of the season. (Opening drives in the 49ers’ five games this season: touchdown, touchdown, field goal, touchdown, touchdown.)

None of the 49ers’ touchdowns proved more creative than Kittle’s second score, on a 38-yard pass from Purdy after a reverse flea-flicker early in the second quarter. The scoring sequence: Purdy handed the ball off to McCaffrey, who lateraled it to Deebo Samuel on a reverse, with Samuel immediately lateralling it to Purdy, who launched his pass at the 50-yard line and took a hard hit from defensive tackle Osa Odighizuma.

The 49ers’ 14-0 lead didn’t last long. Within 5 ½ minutes, Prescott produced a touchdown by attacking the 49ers defense’s most suspect area this season: nickel back. Prescott threw a 26-yard fade pass over Isaiah Oliver and to KaVontae Turpin at the right pylon. The 49ers would not let Dallas dare get any closer.