The ball game ain't started, let alone over, until the tall pitcher sings in Cleveland this Sunday.

Rick Waits, 6-3, 195-pound Indian left-hander whose 2.48 earned run average is fourth best in the American League, has been testing his vocal pitch with Rocco Scotti, who has sung "The Star Spangled Banner" in operatic range before games in several major league parks. And, after Scotti sings the Canadian anthem before the Toronto-at-Cleveland doubleheader, Waits will come on with our national anthem.

Scotti says Waits, 25, " has a terrific voice, a real God-given talent," and Ruben Caplin of the Cleveland Institute of Music agrees the hurler has a future in singing if he works hard at it.

Meantime, the largely unsung Waits will settle for a pitching victory Friday night over the Blue JAys that would boost his record to 5-7 . . .

And the Detroit Tigers are warbling the blues again over mark (Bird) Fidrych. The colorful righty has returned from Florida workouts with little or no improvement in the tendinitis that has kept him off AL mounds since April. "Plans for his future are very uncertain," said a Tiger spokesman who, when asked if Fidrych was throwing the ball, amended."He's lobbying. He has no velocity and has pain." . . .

Heavyweight cochampion Leon Spinks makes himself at home in Philadelphia, Detroit, St. Louis and Jacksonville, N. C., near Camp Lejeune where he served in the Marines. You guessed it. Spinks, driving a 1978 Cadillac, was stopped at 2:50 a. m. yesterday in the North Carolina town - no license plate and, it developed, no driver's license. Just a nice quiet arrest this time, he paid $25 fine and $27 in court costs and see ya later . . .

It's "go" for next Wednesday's fight card at the D. C. Armory, apparently, since headliner Sugar Ray Seales unanimously outpointed Tommy Howard in their Seattle 12-rounder Tuesday night to retain his Northwest middleweight title. Seales, a '72 Olympic gold medalist, is now 47-4-2 as a professional; another of the crop of '76 Montreal goldies, bantamweight Leo Randolph, made his pro debut on the same card, scoring a second-round TKO . . . When Seales and Ralph Paladin go at it, they will be doing so in a newly rededicated Starplex. The District observed a "day" for the complex yesterday, and the luncheon marked maybe the last visit of George Allen to RFK Stadium until he brings his Rams with him. Allen allowed it felt "strange" knowing that . . .

Earl Anthony, the pro bowler who shares Tacoma, Wash; as hometown with Seales and Randolph, was listed in "fair and stable" condition in a San Francisco area hospital yesterday after suffering chest pains while practicing his craft a day earlier. While he, we trust, recuperates, his successor as PBA money-winning champ, Mark Roth ($95,190 to date) has a shot this week at repeating as a $100,000-a-year tour earner in the San Jose Open; only Anthony before him eclipsed $100,000, and the Earl is at $71,188 for the 1978 . . .

Those American U. basketball Eagles get around in the coaching ranks. Now Bill Kagarise, AU '70, has been named head coach at Mclean High replacing Doug Crupper, who will coach hoops at Reston's new South Lakes H. S . . . Washington's finest cont'd: 1978-79 basketball captain at Jacksonville U, is Anthony (Cricket) Williams; incoming Coach Tates Locke saw right away the senior-to-be out of McKinley High has leadership qualities; and at Boston U., the captain will be Curtis Vanlandingham, 6-7 forward from Potomac High and Hillcrest Heights.

The NBA teams who are out of it might cast a new glance at Coniel Norman, the former 76er guard who was the Bullet's last cut of preseason. Norman has been named to the five-man Eastern Association all-star team after a campaign for Lancaster, Pa., capped by amazing 91 percent shooting - 31 of 34 from the field - in the Roses' two-game playoff sweep of Long Island.