Willie McCovey hit only 12 of the 117 home runs the Giants swatted last season. It was a modest output for a chap who used to lead the National League in that department. But they cheer a little louder when Willie hits one.

McCovey's 35-ounce bat is weighted now by his 41 years, and Giant fans allow him points for that. There is nobody else around who is attempting to play major league baseball at that age.

They haven't stopped cheering for Willie since he came to San Francisco 21 years ago as a tallish young first baseman. His trademark was the big hit when the Giants needed it.His teammate Willie Mays used to outhit McCovey sometimes by 50 points, and bunt and steal bases and do all those other things. But Mays was not even the most popular Willie in town. McCovey was.

Perhaps this was because McCovey was homebred, not a player who came to San Francisco from the East as an already certified big-shot hero whom The City's fans were supposed to accept on sight. San Franciscans consider themselves pretty sophisticated about the game -- they saw Joe DiMaggio and Frank O'Doul come up in their town -- and were not going to be awed by a Willie Mays.

Eventually, they cheered Mays, too. Who could ignore all those wonderful skills? But he never gained the folkhero status reserved for good, reliable Willie McCovey who was not only bouncy around first base, but was the man they liked to see to go the plate even if he didn't have that.300 average.

This year the Giants' official brochure, in an evident attempt to mollify Mays or any others, says of McCovey, "Possibly the most popular player in the history of the San Francisco Giants."

But things don't look too well for McCovey this year in the Giant camp. For the first time first base doesn't belong to him. Young Mike Ivie has it, because he outhit the slumping McCovey (.228) by 80 points last season, and now is regarded as one of the NL's rising stars. Manager Joe Altobelli had to pay attention when Ivie frankly demanded the job this year.

And finally, there's a clash of emotions among San Francisco fans so long so completely loyal to McCovey. They still venerate the old guy, but last year they got a strong taste of the pennant when the Giants were in first place longer than any other club, before fading to third. Realistically, they prefer to see Mike Ivie at first base rather than good old Willie, at his age.

McCovey says he isn't through, even at 41, and even if the San Francisco Examiner's poll of the Giant players showed a solid preference for Ivie as the team's first baseman. "You got to remember," McCovey said, "that some men are older at 41 than others."

As for the bedeviling.228 he hit last year, McCovey blames it on a shoulder injury he suffered in August, ducking a pickoff play at second base. Up to the All-Star Game break, only one player in the league had driven in more runs than Willie, but he didn't have the same free swing after he was hurt. He says it has come back.

Ken Hotzman of the Cubs offered a tribute this week to McCovey when he said, "I still don't particularly care to pitch to him."

Two years ago, Giant owner Bob Lurie brought McCovey back to the Giants from San Diego where he had a dismal season (.208). Everybody was certain it was sheer sentiment toward the Giants' former favorite who then was 39. But what a year Willie gave them. Twenty-eight homers and a.280 average. He was voted the NL Comeback Player of the Year, 17 years after he was voted Rookie of the Year.

Meantime, Willie had hit 18 grandslam home runs, an NL record. No other player ever hit two home runs in the same inning twice. But the one swing all the world remembers was the ball he hit in the 1962 World Series against the Yankees, two out in the ninth and the tying and winning runs on base. Willie caught a pitch on the nose. a blue darter, only to leave Giant fans gagging on their own cheers when Bobby Richardson lunged to spear it for the final out.

The other day in the Giant camp they asked McCovey the inevitable question: Who was the toughest pitcher he ever faced and he said, "(Sandy) Koufax, before he gained control."

On second thought, however, McCovey said his absolute worst memories were of facing Bob Veale, Pittsburgh's hard-throwing, but wild, lefthander. It was worse, McCovey said, because every hitter knew that Veale, in addition to everything else, also has poor eyesight.