It's only April, but the Baltimore Orioles are playing September baseball. Ask the Toronto Blue Jays.

Eddie Murray's three-run homer in the eighth inning today gave Baltimore a dramatic 8-7 comeback victory over Toronto at Memorial Stadium.

Minutes after the Orioles had stretched their record to 4-0, matching their best start in a dozen years, the crowd of 28,529 still was chanting "Eddie, Eddie, Eddie" as Murray peeked from the dugout and doffed his cap.

His home run was the first by an Oriole in 53 plate appearances against relief ace Bill Caudill.

"I like being in that pressure spot," Murray said. "I don't mean I want to carry the whole load, because you start thinking if you don't do it, no one else will.

"He kept the ball away from me and I was being selective. It paid off."

Caudill said he wanted to get Murray, a switch hitter batting left-handed, to hit to the opposite field, left field.

"It was a 3-2 count and you have to go with your best pitch," Caudill said. "He hit the ball on the button. I can't hang my head . . . Murray's a great hitter. But's it's hard to take."

While Murray was circling the bases, left fielder George Bell, who had leaped in vain for the ball, threw his glove in the air in frustration.

The Blue Jays had every reason to be frustrated. A good effort by starter Dave Stieb (two runs in six innings), a six-run inning by the Blue Jays and a bases-empty home run by Bell put them ahead, 7-2, going into the bottom of the eighth.

Then the Orioles had their own six-run inning. Fritz Connally opened by reaching on an infield hit off reliever Jim Acker. Rich Dauer walked. Rick Dempsey then lined a single to make it 7-3. Exit Acker. Enter Caudill, who walked Mike Young to load the bases with none out.

Dauer scored the Orioles' fourth run when pinch hitter Jim Dwyer bounced out to first. Things were getting serious for Caudill, especially with Cal Ripken and Murray due up.

Ripken pulled a fast ball that caromed off third base into short left field, scoring Dempsey to make it 7-5.

Up stepped Murray, who came into the game with only two hits this season, although one was the game-winning two-run homer in the season opener against Texas. With the count full, he sent a fast ball over the left-center field fence.

"There were only two balls hit well in the inning," Toronto Manager Bobby Cox said. "One sneaked up the middle, one hit the bag and another was fisted down the line. Bell just missed the ball; the wind helped take it out."

Reliever Tippy Martinez earned his first victory of 1985, but not before teasing the Blue Jays in the ninth. They got two runners on via a single and an error before pinch hitter Garth Iorg lined out to shortstop Ripken to end the game.

"I just went in to throw some strikes and get some work," Martinez said. "Before you knew it, we were scoring and it was a game again."

It was a game early, too, as Orioles starter Storm Davis looked tough through three innings. The Blue Jays' only base runner in that time was Lloyd Moseby, who walked in the first. Davis retired eight in a row before again walking Moseby in the fourth. That started his trouble.

The next batter, Willie Upshaw, doubled Moseby to third. Bell sent a hard grounder down the third base line, which Wayne Gross' diving stop held to a single. But Moseby scored on the play to make it 2-1.

Ernie Whitt chased Bell home with a line single to center to tie the game at 2. Designated hitter Willie Aikens then doubled off the top of the left-center field fence to score another run.

The Orioles' pitching coach, Ray Miller, visited the mound and decided to leave Davis in. Up came Jesse Barfield, who put a three-run homer into the stands to give Toronto its 6-2 advantage.

"The ball hit off Storm for the home run was a 91-mile (per hour) fast ball," Baltimore Manager Joe Altobelli said. "He wasn't losing anything. He had pitched no-hit ball for three innings and it's tough to take a guy out when he's throwing at 91."

Thanks to Murray, it didn't matter.