On a night Scott McGregor made the art of pitching look easy, the Baltimore Orioles made winning look easy.

After scoring three or fewer runs in eight of their first 18 games, they brought out their 1985 bats tonight, pounding the Chicago White Sox for 12 hits and an 8-1 victory before 11,397 at Comiskey Park.

McGregor (2-2) didn't need much support as he pitched his team's third complete game, allowing the White Sox four hits in a no-walk, four-strikeout performance.

And for a while, it appeared he wouldn't get much. White Sox starter Gene Nelson (1-1) was a last-minute replacement for Tom Seaver, who was called to Fresno, Calif., because of the death of his mother, and Nelson matched McGregor's shutout for five innings.

In the final four, though, the Orioles had one of their best offensive showings of the year, scoring a run in the sixth, four in the seventh and three in the eighth.

They got two-run home runs from Cal Ripken and Floyd Rayford, and of their 12 hits, six were for extra bases.

"Hitting is contagious," Ripken said. "I don't care what anyone says. That's the truth. When you're struggling, everyone goes to the plate with the idea of picking everyone else up. When the whole team is hitting, you go up there with a nice relaxed feeling."

Besides Rayford's first homer of the season, the Orioles' best news was from Larry Sheets, who has apparently won his designated hitter spot back and tonight was on base four straight times with a single, double, triple and walk to raise his average to a team-leading .360.

McGregor had pitched a total of only 8 1/3 innings his last two starts, allowing 12 hits, nine earned runs and four homers (9.72 ERA). He had looked bad enough that one more bad start might have sent him to the bullpen, and Dennis Martinez into the starting rotation.

Through the slump, he insisted he had been pitching well even if the results didn't look so good, and tonight the left-hander was three outs away from a shutout when Wayne Tolleson hit his fifth career home run.

That was only the fourth Chicago base runner of the game. This was vintage McGregor, using 111 pitches and getting 15 of the 27 outs on flies and popups.

"I had good stuff, no doubt about it," he said. "This is the way I felt through the last part of spring training. I kind of lost it for a few games, but I'm back in a groove."

McGregor went back and looked at films of himself in 1983, and he said, "Sometimes looking at the films helps because you realize you're not pitching as badly as you think."

Manager Earl Weaver aslo had had McGregor out throwing batting practice since his last start, and Weaver said that was one of the keys to his success.

Weaver was four feet away from McGregor, piling sliced roast beef on a slice of bread, when someone asked about pitching batting practice.

"If he thinks it helps, let him think that," McGregor said, loudly enough Weaver could hear. "I know I didn't get anyone out throwing batting practice. He says it's no more taxing on our arms, but . . . "

Back in Weaver's office, the manager said, "I've been around long enough to know it helps. I think it's idiotic to say it doesn't."

Meanwhile, the Orioles were making all kinds of noise but not scoring until the sixth, and going zero for nine with runners in scoring position until the seventh.

They got a 1-0 lead in the sixth, an inning begun with Lee Lacy's single to right field and Ripken's ground single to center. Eddie Murray forced Ripken at second, putting runners at first and third.

And Nelson almost got out of that inning, too. He got Fred Lynn to hit a slow dribbler toward second baseman Julio Cruz, who flipped to Ozzie Guillen for one out. Guillen's relay to first, though, was too late and too wild, and Lacy scored.

The Orioles broke it open with their four-run seventh.

Sheets walked and Rick Dempsey sacrificed. Rayford grounded out, but just when it looked as if he might escape again, Nelson walked Juan Bonilla and allowed Lacy's two-run double to left for a 3-0 score.

"I thought Nelson pitched great," said White Sox Manager Tony LaRussa, whose team is 6-12. "Considering he was coming out of the bullpen, I was only planning on getting four [innings] out of him."

Nelson's line would have been better had reliever Dave Schmidt not come in and immediately allowed Ripken's two-run upper-deck home run to make it 5-0.

The Orioles got three more off Schmidt in the eighth. Lynn doubled, Sheets tripled and Rayford cleared the center field fence with his first homer of the season.

Before the game, Weaver had complained about the Orioles' lack of home runs, saying, "I can remember everyone who has hit one."

After the game, he said, "I still can remember everyone who hit them tonight -- Rayford and someone else. We had to start hitting with men on base sooner or later."

With Atlanta's Dale Murphy getting hurt, Ripken should have the major leagues' longest current streak of consecutive games. Ripken played in his 622nd straight tonight, and Murphy's will apparently end at 675. Ripken has played 5,623 innings without relief, believed to be an all-time record . . .

Second baseman Alan Wiggins (.194) was benched for a third straight game, and Weaver said he won't rule out playing Wiggins in the outfield if Bonilla continues to play well . . .

Reliever Tippy Martinez underwent a spinal test Monday at Johns Hopkins Hospital in Baltimore, and doctors still haven't found an exact cause for the dizzy spells that have him on the 21-day disabled list. "I'm feeling better today," he said. "They're giving me medicine for a viral infection."