SEATTLE -- It was a small thing, but an unmistakable act of love. Ken Griffey Jr. carried a towel over to the batting cage and gently mopped the tiny rivers of sweat that ran down the face of Ken Griffey Sr. As he did so, you could see the vast admiration of a son for his father.

The bond between them was apparent, in their glances, warm smiles and good-natured banter while dad practiced hitting in a near-empty Kingdome after Wednesday's game.

For both Griffeys, it was a moment they had hoped for: They would be playing baseball together now -- like they did so many years ago when father took son out to the back yard for their first game of catch. Only this time, they were doing it in the big leagues.

"Being a father, I guess it's a dream come true," Griffey Sr. said about playing professional baseball with his son. "This is the pinnacle -- this is the thing in my career that I'm very proud of -- very proud of. You can talk about the '76 batting race I was in and all that. But to me this is number one. Even the World Series I played in -- the two of them. This is number one for me."

As usual, Griffey Jr. wouldn't say much about his feelings. But the shy, 20-year-old center fielder who's become a major league sensation didn't need to. "It's something he's always wanted since I became a professional," he said. "He's finally got it. I'm just glad I'm his son."

The Mariners made history Wednesday by signing Ken Griffey Sr. as a free agent. They are the first father-son combination in major league baseball to play on the same team at the same time. It was the second historical achievment for the Griffeys. Last year, when Griffey Jr. made Seattle's roster, they became the first father and son to play at the same time in the majors.

Griffey Sr., 40, was released Aug. 24 by the Cincinnati Reds. When he cleared waivers Wednesday, Seattle grabbed him. He comes to Seattle with valuable experience. He played a major role with Cincinnati's "Big Red Machine," which won the World Series in 1975 and 1976. Griffey Sr. also played for the New York Yankees and Atlanta Braves.

With the Reds this season, he hit just .206 with one home run and eight RBI in 46 games. Still, Seattle Manager Jim Lefebvre sees Griffey Sr. as an excellent addition to the Mariners, and started him with his son Friday night at home against Kansas City, a game Seattle won, 5-2.

It was a dream debut, for both men.

"It seemed like a father-son game," Griffey Jr. said. "It seemed like we were out in the back yard playing catch. . . . I wanted to cry. It was his day."

The Griffeys had a bet on who would get the first hit, Ken Sr. winning a dinner from his son. With one out in the first inning, Griffey Sr. singled and Griffey Jr. followed with another single. Both scored. "The first time up, I was really nervous," Griffey Sr. said. "It was like being a rookie all over again. There wasn't any pressure, just butterflies."

In the sixth inning, the elder Griffey threw out Bo Jackson trying to stretch a single into a double. He cleanly fielded the ball off the bullpen wall in left field and threw a strike to second baseman Harold Reynolds.

Griffey Jr., the American League's all-star center fielder, yelled to his father, "It runs in the family."

Even Jackson was caught up in the emotion of the night. In defeat, he had a smile on his face. "I didn't expect a perfect bounce off the wall and to have that old guy throw me out," he said. "I'd have been mad if anyone else had thrown me out, but it was a piece of history. Those Griffeys were messing with me."

Clearly, there was more than just sentiment involved in the decision to reunite the Griffey family.

"I want to make it perfectly clear: He's not here just so we can say we have the first father and son," Lefebvre said. "He's here to make a contribution. If I were to look out there in the baseball world and say, 'I want somebody who is a winner; a player who could come and be a strong influence on our young players -- it would be Ken Griffey Sr."

Plans are to use Griffey Sr. as a left fielder, designated hitter and pinch hitter, Lefebvre said.

"He's going to make a contribution not only on the field, but in the clubhouse," Lefebvre said. "He's going to help our younger players and the organization get where we want to be, and that's a world championship.

"He's here to make a contribution to the overall plan and I mean that sincerely. We're thrilled to have him, his leadership and what he represents."

His new teammates also seem thrilled. "I think it's great that Kenny came over to play with his son," first baseman Pete O'Brien said. "It's great for the game. He's been around a lot longer than a lot of us. Anything that we haven't gone through I'm sure he's gone through, and that helps."

Added outfielder Jay Buhner: "He's a true veteran. He'll be out here providing a little leadership. . . . You can go to him and ask questions. He's been around enough to where he's got good advice."

The Mariners have been trying to acquire Griffey Sr. since last offseason, General Manager Woody Woodward said. They've wanted him not just for his leadership, but because he also gives the team more left-handed hitting.

Griffey Sr.'s obvious influence on his son also has the potential for creating some problems, but he said he's not there to usurp the manager's or the coaches' authority.

"It's going to be totally professional out on the field," he said. "I'm going to let Jimmy handle him."

Then he flashed a grin, looked Junior in the eye and added that there might be some exceptions: "When we get out in the field and I have to call him off a fly ball or something and he doesn't listen to me, then I might have to straighten him out."