BALTIMORE (Ticker) -- The Baltimore Orioles gave Johnny Oates a warm reception and Roger Clemens a rude one.

Scott Erickson, who was making a return of his own, pitched six strong innings and Tony Batista belted a grand slam off Clemens to give the Baltimore Orioles a 10-3 victory over the New York Yankees.

The ceremonial first pitch was thrown out by Oates, the former Orioles manager who recently underwent surgery to remove a brain tumor. An emotional Oates held back tears as he received a long ovation from the sellout crowd at Camden Yards.

"I have a special affinity for him, for his work ethic and the way he treats people," Orioles manager Mike Hargrove said. "I was happy to see him."

Oates gave way on the mound to Erickson, who missed all of last season after undergoing "Tommy John" surgery on his right elbow. Making his first appearance since July 25, 2000, Erickson allowed just one unearned run and three hits while walking five.

"It's been a long road, but it was important to get things out of the way," said Erickson, who had nine ground ball outs.

"I worked today on location and keeping the ball down. Keeping them off the bases helped, too."

Erickson (1-0) got help from Batista, who belted his sixth career grand slam and first by an Oriole on Opening Day since Eddie Murray in 1982.

Clemens, who was making his 12th Opening Day start, struggled with his control after he tried to barehand a ground ball by David Segui that went for an infield single in the fourth.

Clemens walked Jeff Conine and Jay Gibbons before Batista homered to left-center field on the first pitch.

"I saw he was walking batters. I decided to swing at the first pitch when I got up there. It was a fastball right there," Batista said. "It was a good day for the team and a good day for me. I am happy."

The Orioles were able to contain Jason Giambi, baseball's prized free agent, who signed with the Yankees in the offseason. The first baseman was 1-for-4 with a walk and grounded out with the bases loaded to end the fifth.

"I was excited to be out there. I just let the game come to me. The game didn't change. Just the uniform," said Giambi, who lamented his groundout in the fifth. "Any four-letter word would have hit the moment after I hit it, but you have to give Erickson the credit there."

Baltimore added another run in the fourth when Melvin Mora walked and later scored on a run-scoring single by Geronimo Gil.

Clemens allowed a single and two more walks in the fifth and Mora broke the game open with a three-run double that made it 8-1.

After the game, Clemens was taken to a hospital for precautionary X-rays, which were negative. Clemens, who allowed eight runs and seven hits in 4 1/3 innings, has swelling in the hand and is listed as day-to-day.

"He got hit in a pretty good part of the hand," pitching coach Mel Stottlemyre said. "He's got a bad habit of doing that his whole career. It's just a reflex action."

Derek Jeter played a part in all three New York runs. He stole third in the first inning and scored when the throw by catcher Gil went into left field.

Jeter hit his 100th career homer in the eighth, a two-run shot off Rodrigo Lopez that also was his 1,200th career hit.

"It just didn't happen for us today," Jeter said.