The Mighty Irish flexed their muscles and pounded Navy into the Notre Dame Stadium turf today, 43-10.

It was Navy's worst beating of the season, and the Mids were beaten physically, mentally and every other way imaginable.

Notre Dame, 6-1 and striving for the national championship, never had to exert itself.

"It was pretty hard to get back to earth after last week," coach Dan Devine said, referring to last Saturday's 49-19 victory over Southern California. "I was genuinely concerned about a possible letdown."

A Notre Dame letdown was about all Navy could hope for, but it didn't happen.

The Irish gave the Mids no slack as they piled up 468 yards and held their opponent to 193, with a healthy chunk of the latter coming in the fourth period after the outcome had long been decided.

Even the score, as lopsided as it was, misleading. The Irish fumbled away the ball twice, threw two interceptions and failed to score on two other drives when they had the ball at the one- and two-yard lines.

"They were just better than us. There's no doubt," said Navy coach George Welsh. "They handled us. They are just so strong physically that there wasn't much we could do with them.

"And their defense," he said, forcing a smile and shaking his head. "You can't do much of anything against it. Even when we made some running room and got some blocks, we only picked up four or five yards. When they hit you, you stop."

Notre Dame, playing in green jerseys for the second straight week, got 100 yards rushing from Jerome Heavens on 17 carries that included a 49-yard first-quarter run for Notre Dame's first score.

Quarterback Joe Montana completed 11 of 24 passes for a career-best 260 yards, and a touchdown. Montana scored himself on a one-yard run.

All-America tight end Ken MacAfee caught five passes for 130 yards and no Navy defender was anywhere near him on any of them.

"I don't know where they were," MacAfee said.

Welsh was left wondering where his offense had gone, but after reflecting on the strength of Notre Dame's defense, conceded that his team moved the ball about as well as it could have.

Navy quarterback Bob Leszcynski, who completed 21 of 45 passes for 294 yards last year against Notre Dame, was a disappointing seven for 22 today for 55 yards. He had three passes intercepted.

"We didn't sneak up on them like we did last year," Welsh said.

The Mids' situation was best illustrated in the fourth period when three straight personal-four penalties on the Irish gained Navy 45 yards. Even then, the Mids couldn't get beyond Notre Dame's 31-yard line.

Navy's only touchdown came on a six-yard pass from reserve quarterback Bob Powers to Phil McConkey with 1:54 left. Bob Tata's conversion made the score 36-10, but the Irish got the score back 1 1/2 minutes later when linebacker Leroy Leopold picked off a Powers pass and rambled 50 yards into the end zone.

Tata accounted for [WORD ILLEGIBLE] other three points on a third-period field goal that came when the Mids were down, 23-0.

Thanks to two marvelous goal-line stands in the first quarter, Navy escaped the first half trailing only 16-0. Heaven's run and three Dave Reeve field goals and an extra point accounted for the scoring.

The Mids had the ball nine times in the first half and each of their possessions ended in one of two ways - either Art Ohanian had to punt (seven times) or Notre Dame cornerback Ted Burgmeier intercepted a Leszczynski pass.

Navy made only two first downs in the first half and reached Notre Dame territory once. That came on an interception and 35-yard return to the nine-yard line by linebacker Tom Paulk.

Three plays later, however, with Ross Browner hanging all over him, Leszczynski thre a dead-duck pass toward John Kurowski in the end zone. Bergmeier stepped in front for the interception.

Terry Eurick returned the second-half kickoff 42 yards and, five plays later, Montana scored on a quarterback sneak.The big play on that drive was a 48-yard pass to MacAfee.

From then on, the Irish just laid back and had fun. Second-string quarterback Rusty Lisch replaced Montana in the fourth period and he came out throwing. But after he went 3 for 2. Devine tried freshman Tim Koegel. He too went 0-2, but no one seemed to care.