SAN FRANCISCO -- It's not too much of a reach to suggest that without Monte Irvin, there might have been no Willie Mays.

When Mays was summoned to the New York Giants on May 25, 1951, manager Leo Durocher immediately ordered Irvin to serve as essentially the 20-year-old rookie's guardian. Having grown up in the deep South, Mays knew nothing of sophisticated New York. Having played in the Negro Leagues, Mays was unaware of the customs and mores of Major League life.

So it was up to Irvin, then beginning his second full season in the Majors, to steer Mays onto the right behavioral path and keep him there. That set Mays on course for the Hall of Fame career that extended through 1973, Irvin obviously a fine tutor.

"In my time, when I was coming up, you had to have some kind of guidance. And Monte was like my brother," said Mays, the legendary Giants center fielder.

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Irvin's willingness to help his fellow man is worth remembering as baseball observes Jackie Robinson Day. Like Robinson, Irvin strove to maintain a positive example every time he took the field and, as Mays can attest, in life itself.

Irvin made sure that Mays didn't run with the wrong crowd. Mays recalled that Irvin and his wife, Dee, frequently invited him to their home in Orange, N.J., for meals that featured southern cuisine.

"That time was very precious because of him, Leo and my godmother in New York, Ann Goosby," Mays said.

But while Durocher alternately goaded and comforted Mays to get the most out of his ability and Goosby provided him with a wholesome place to live, Irvin served as his true big league mentor, on and off the field. Having joined fellow outfielder Hank Thompson to become the Giants' first black players in July 1949, Irvin knew his way around. And as a Negro Leagues veteran like Mays, Irvin could relate easily to his protege.

"I couldn't go anywhere without him, especially on the road," Mays said. "... It was just a treat to be around him. I didn't understand life in New York until I met Monte. He knew everything about what was going on and he protected me dearly."

Irvin, who's 93 but remained quick with a quip two years ago during the Giants' ceremonies to retire his No. 20, implied that Mays didn't need his counseling for long.

"I did that for two years and in the third year he started showing me around," Irvin said.

But Irvin never stopped commanding respect. In fact, he had been considered a standard-bearer long before meeting Mays or even before reaching the big leagues. Before Irvin served in World War II with the Army Engineers from 1943-45, it was he, not Robinson, who was widely considered the likeliest candidate to integrate the Majors. Why not? His character was beyond reproach. He possessed the tremendous poise that the first black player would need. And it helped that he was a superb ballplayer. He hit .422 and .396 for the Newark Eagles in the Negro Leagues in 1940-41 before leading the Mexican League with a .397 average and 20 homers in 63 games for Azules de Veracruz.

But when Irvin left the Army, he didn't feel ready to resume the height of baseball competition, though Brooklyn Dodgers general manager Branch Rickey wanted to sign him. So Irvin went with Larry Doby to play in Puerto Rico. Irvin quickly regained his skill, winning Most Valuable Player honors in 1945-46. In January 1949, the Giants signed Irvin and Thompson. Two years later, they and Mays combined to form the Majors' first all-black outfield.

In the middle of all that, Irvin and other black players paid close attention to Robinson's rise to the Majors.

"After World War II, I realized that there was a chance [to play in the Majors]," Irvin said. "And, of course, when [the Dodgers] signed Jackie, I knew that was going to be the demise of the Negro Leagues. But we rooted for him because we knew that was part of progress."

At the same time, Irvin ached for the stellar Negro League performers who never received a chance to perform on baseball's biggest stage -- Ray Dandridge, Josh Gibson, Buck Leonard and Martin Dihigo, among others.

"They were superstars," Irvin said. "They would have been superstars in the Majors had they been given a chance. When I had the chance and I succeeded, I thought about them and what great records they would have made if they had been given the chance."

Irvin proceeded to hit .293 in the Major Leagues with 97 doubles, 31 triples, 99 home runs and 443 RBIs. He sparkled in 1951, helping the Giants surge to the National League pennant by hitting .312 with 24 homers and an NL-leading 121 RBIs. He also hit .458 (11-for-24) in the World Series, which the Giants lost in six games to the New York Yankees.

On the left-field facade at AT&T Park where the markers honoring the Giants' 11 retired numbers are mounted, Irvin's is displayed next to Mays' familiar No. 24.

"I feel like my life in baseball is complete," Irvin said as he observed this tribute.