Rookie third baseman Chris Pittaro, who had never set foot on a major-league field, got three hits yesterday to enable the world champion Detroit Tigers to beat the Cleveland Indians, 5-4, in their season opener before 51,080 in Detroit.

Pittaro, 23, who played AA ball last season, drove in the tying run in an eighth-inning rally.

"Hopefully, this says I can hit major league pitching," he said.

"This is the Chris Pittaro story," his manager, Sparky Anderson, said. "See, we were all worried about him. Now, he's a man."

Otherwise, the Tigers looked like they did last season when they won 35 of 40 their first 40 games. Willie Hernandez, the AL's Cy Young winner and most valuable player, got the save by getting the last three outs in relief of winner Jack Morris. But Anderson had to check out of a hospital to be in the dugout.

His Tigers trailed, 4-3, in the eighth when Larry Herndon singled off Cleveland's Tom Waddell. After Ernie Camacho relieved and walked Chet Lemon on four pitches, Pittaro's third single -- off a low fast ball -- tied the game and sent Lemon to third. Lou Whitaker followed with a sacrifice fly that won the game for Morris.

"Pittaro hit a good pitch," Camacho said. "I would throw the same one to him again. Give him some credit."

Anderson left the hospital yesterday morning after Clarence S. Livingood, the team physician, decided the problem with his swelled left leg is merely "pseudo-gout."

"I slid out of bed this morning and tested it," Anderson said. "It was stiff . . . But I've never missed an opening day and I wouldn't want to miss this one. It's a day we're going to get the rings."

"Now we just have 161 more games to go," Morris noted after the team got its 1984 World Series rings.