A relaxed and confident band of Kansas City Royals panned the New York Yankees' ears back today, 7-2, to open the American League playoffs.

The Royals played as though each of their underrated stars wanted to give the watching nation a one-game synopsis of his skills.

"Well," drawled big John Mayberry, who crunched a 450-foot homer that landed in another zip code area, when the second hitter of the game hits a two-run homer to get you started, and then you come within an inch of ending the game with a triple play, I guess you've given the other team a fair look at what you can do.

"This team's been riled up for two months and we keep amazing each other with what we can do."

The Royals, as is their habit, shared the spotlight a half-dozen ways. Hal McItae blasted that first-inning homer, a 400-foot shot after Fred Patek's game-opening walk. Al Cowens, who jumped above the right field fence to take a home run from Mickey Rivers, later hit a solo homer to the same spot behind the 387-foot sign where the McRae ball landed.

"Both of 'em hit the NBC cameraman out there behind the fence," said Royal sub Joe Lahoud with a laugh. "We figure that's bringing the game right into the living room."

When the Royals' 5-foot-4 Patek was not leaping to snag line drives or knocking in two runs with a double over the third base bag, then Joe (Who) Zdeb was stealing a base head first or Frank White was chasing down a tough pop-up.

Giving stability and a stoic calm to the entire Kansas City effort was 6-foot-3 southpaw Paul Splittorff, who cruised through the first eight innings. He chewed up the Yanks lefthanded sluggers and made only one mistake - a two-run gopher ball to Thurman Muson after the Royal lead was already 6-0.

Splittorff, 30, was a blond, clean-cut, middle-America grim reaper sending the despised Yanks down inning after inning with hard stuff to the lefthanders and change-ups to the righties.

His tell-tale curl of the lip as he fired epitomized the Royals barely disguised distaste for the New Yorkers.

"I'm just a streaky pitcher," explained Splittorff with a grin. He has won 16 of his last 18 decisions. "I seem to pitch as well as the club behind me plays. I keep my team in the game, but I don't win it by myself. I need support."

And today he got it. The Royals scored two runs in each of the first three innings, almost salting away the game before it was one-third finished.

Royals manager Whitey Herzog looked brilliant by the time the game was eight pitches old. "I don't want to imply that I'm a genius," said Herzog, "but I did bat Patek leadoff today because (Don) Gullett sometimes starts off wild high, and Patek did draw a walk on four pitches. And the second man did hit it out of the park."

The contrast with last year's Yank-Royal playoff was inescapable. In the top of the first in '76 in KC, the Royals' George Brett made an error that led to a quick 2-0 Yankee lead. After that opening loss at home, the Royals had to fight from behind through the entire five games.

The Yankees need look at only one statistic to judge their position accurately. No team in playoff history has lost an opener at home and come back to win.

"The thing about us that is striking," said Splittorff, who allowed eight hits before getting ninth-inning relif help from Doug Bird, "is how much we've settled down since last year."

In fact, it was the Yanks, perhaps shaken by recent manager-owner conflicts, who looked uncharacteristically rocky.

The Royals' two second-inning runs, the only scores not produced by homers, were the result of awful Yankee judgment on defense. With one on and two out, the normally exemplary Graig Nettles backed up and let Frank White's easy hopper to third play him. His force-play peg to second was beaten by hustling catcher Darrell Porter, who has hit .440 against New York this year.

Next Patek, the first-inning thorn, came back to haunt Gullett again. The 14.4 lefthander with the best career winning percentage in baseball seemed to have the littlest major leaguer on the ropes after two blazing strikes.

But the scrappy Patek laced a Gullett fork ball on two quick hops over third. Only one run should have scored, but left fielder Lou Piniella approached the ball lazily, then tossed it back to the infield sidearm, mistakenly thinking that the left field umpire had ruled a fan had touched the ball, making it a ground-rule double.

White, in typical Royal style, never hesitated, scoring just as Piniella's face began to turn an embarrassed crimson.

The Royals' defense almost matched its offense for panache. Right fielder Cowens, the Royals' unheralded team MVP who had three hits today, stretched to the top of nine-foot wall for a Piniella fly in the third, then jumped inches above it for Rivers' drive in fifth.

Brett barely missed a final defensive coup de grace when he started an around-the-horn double play in the ninth that missed tripling up batter Willie Randolph at first by half a heartbeat. "We'd have loved that," Mayberry admitted.

The Royals loved this one anyway, pounding each other's backs and slapping hands as though a World Serious had been won.

"This is an old-fashioned team in modern uniforms," exhulted Lahoud. "I've been with five teams, but never one half this close-knit. We harass rookies like the old-timers did. We needle each other. We take the extra base and slide spikes up. If you knock down one of our hitters, we knock down two of yours."

The Royals' first act in victory was to award its daily booby prize - The Gong. "Splittorff gets it," crowed Lahoud. "He messed up two double-play balls hit back to him and walked the leadoff man in the ninth. But McRae was a close second. He missed first base and had to go back to tag it on his homer."

Splittorff, who had just muffled the Yanks' lefthanded big three - Nettles. Reggie Jackson and Chris Chambliss - on one infield single in 11 at bats, welcomed his gong in good grace.

For the Yankees, who will start Ron Guidry against either Andy Hassler or Larry Gura on Thursday [WORD ILLEGIBLE] (8:15 p.m. EDT), Herzog had a final thought. "We've played better. said. after this almost flawk ramp. After a long pause, the [WORD ILLEGIBLE] finally thought of a mistake had a suicide squeeze bunt roll [WORD ILLEGIBLE] he said.