Defense began to lose its grip on pro football Sunday.

There were big offensive plays, six individual 100-yard plus rushing performences; hard wear on some quarterbacks and a couple of game officials.

Redskins viewing the Dallas Cowboys - St. Louis Cardinals game film will see that Tony Dorsett is just about ready to give defenders the shakes on Sunday mornings.

The dormant Cardinal assault force finally came to life in the first quarter as coach Don Coryell ended Terry Metcalf's role as a spot player. Metcalf ran a quick counter trap play to the Cardinals' weak side and 62 yards later St. Louis had a 10-3 lead.

Play-caller Lanory then went to his bench for Heisman Trophy winner Dorsett to assist Heisman Trophy winner Rodger Staubach with a Randoff from the Information. Seventy-seven yards later, Dorsett had the tying touchdown as several would-be tacklers came up empty handed, the last of whom was cornerback Roger Wehrli.

As if sensitive to those who have suggested he is a bit light for the job at 5-foot-11 and 192 pounds, Dorsett said, "I had momentum and they were not going to stop me that way," (what arm tackles).

Despite coming into the game with a 6.9-yard rushing average for 21 carries and averaging 30.7 yards on three carries in the first half Sunday, mostly because of his runaway touchdown, Dorsett languished on the bench behind 32-year-old Preston Pearson until there were only 2 minutes 11 seconds to go in the third period.

His average "slumped" to slightly less than six yards a carry the rest of the way, but he did score the touch-down that cut the Cardinals' lead to 24-23 at the outset of the 14-point fourth quarter that won for Dallas, 30-24.

Six-season veteran Robert Newhouse could not bump the ball over from a yard out with his compact 205 pounds, but Dorsett leaped over marining tacklers on second down.

Dorsett, others who rushed for more than 100 yards on Sunday were Benny Malone of Miami, 139; Lydell Mitchell, Baltimore, 142; O. J. Simpson, Buffalo, 122; Herb Lusk, Philadelphia, 117, and Sam Cunningham, New England, 101.

Besides Hart and Staubach being shakenup, quarterback Terry Bradshaw and Mike Kruczek of Pittsburgh and Dan Pastorini of Houston came out of that contest as casualties who do not figure to play for a while. Bradshaw suffered a broken left wrist, Kruczek a dislocated and separated shoulder, and Pastorini a severely sprained ankle.

The Steelers signed quarterback Neil Graff, whom they had cut in the preseason, today and were vague about when Bradshaw might return to action. "It's very difficult to say," said coach Chuck Noll. "I have yet to be given a true time frame."

Pastorini is expected to practice this week.

Even head linesman Dave Hawk was injured in that game when he tried to break up a fight between Steeler lineback Jack Lambert and Oiler Carl Mauck. Lambert said he hit Hawk inadvertently. The official departed bleeding from his face and with a concussion. Lambert suffered a bloody nose and a cut on his forehead.

Umpire Ralph Morcoft was shaken up by a collision in a punting play in the Cowboy-Cardinal game.

In other offensive highlights, Mike Fuller of San Diego scored on an 88-yard punt return; Freddy Soloman, Miami, ran back a kickoff 86 yards for a touchdown; teammate Malone ran 66 and 52 yards for touchdowns; Mitchell of Baltimore ran 55 yards for one touchdown and 33 another time; Lusk of Philadelphia, 70 for a score; Jimmy Robinson of the New York Giants scored on an 80-yard pass play; Keith Krepfle of Philadelphia on a 55 yard pass, and Sammie White of Minnesota scored on a 50-yard run with a lateral flipped deep to him by wide receiver Ahmad Rashad, who had caught a pass for a nine-yard gain.