Willie McCovey seems eternally and eminently upbeat despite grueling physical issues that have taken a toll on his body but not his spirit.

Baseball has been a saving grace. A Giants senior adviser, McCovey has been a regular at AT&T Park, where he’ll sit with his girlfriend, Estela Bejar, in a press-box booth overlooking the diamond, McCovey Cove and a statue depicting his majestic swing.

McCovey turns 80 on Wednesday, and he’ll celebrate a distinguished life featuring a Hall of Fame career and love affair with a city and fan base that started with his 1959 rookie season and continued through four decades in retirement.

“Baseball helps a lot, for sure,” said McCovey, the memory still fresh of a serious infection three years ago that nearly took his life. “My first day back to the ballpark (for a 2014 playoff game) after I went through this was like heaven, and I was still on a gurney.”

McCovey expressed mounds of thanks to doctors “for saving my life,” performing successful surgeries and reviving him after his heart stopped three times.

“It almost killed me,” McCovey said of the infection. “It had spread, and they had to take all the hardware out of my knees. That’s why I can’t stand now. That’s why they put something in there to keep my legs straight. That’s why I don’t fly anymore, because I can’t sit on an airplane.

“They didn’t think I’d make it at one point.”

The former first baseman must monitor an atrial fibrillation and has undergone so many operations over the years that he lost count, leaving him in a wheelchair. “These knees,” he said, “have been through hell and back.”

Still, he smiles. He chuckles. He rejoices. He overcomes. Always the high road. As if he were the perennial winner of the Willie Mac Award, which goes to the most inspirational Giant.

“Every day is a blessing. Every day, every year,” said Bejar, who met McCovey in 2010, back when she knew nothing about baseball. It didn’t take long for them to fall for each other, and love and laughter have filled the room ever since.

In an interview at McCovey’s Woodside home, he reflected on a legendary career that spanned 22 seasons — starting and ending in San Francisco, with layovers in San Diego and Oakland — and featured 521 home runs and a million memories.

Willie, meet Willie

McCovey remembers first meeting Willie Mays in New York when the Giants still played at the Polo Grounds. Then with Double-A Dallas, McCovey was in New York for the first of many surgeries after injuring his knee and ankle.

“Willie would take me to the pool hall,” McCovey said. “He liked to shoot pool, he and Junior Gilliam. So I would go sit and watch.”

Rather than staying at a hotel, the kid stayed with Mays.

“Everybody looked up to Willie. You know that,” McCovey said. “Why wouldn't you, as a young kid? He was everything in New York at the time. He was Mr. New York. You got a lot of attention when you went out with him.”

Teddy Ballgame’s advice

There was a time the Red Sox trained in Scottsdale, Ariz., meaning the great Ted Williams was hitting balls toward the desert sun. It also meant a young McCovey, whose Giants trained in Phoenix, found a legendary left-handed hitter to go to for advice.

Williams’ last two big-league seasons, 1959 and 1960, were McCovey’s first two.

“I learned from Ted Williams about getting a good pitch to hit,” said McCovey, who was named the National League’s top rookie in 1959. “He was really my mentor as far as hitting. I talked to Ted a lot. I used to talk to him around the cage. He loved to talk. For some reason, he kind of took a liking to me. We were always kind of the same in stature.”

McCovey would ask Williams about his bats and why he’d use certain sizes and weights. Williams, who had taken swing path and bat speed to a new level, encouraged the young McCovey to use a light bat.

“That was Ted’s thing. He said the first thing is bat selection,” McCovey said. “At first, I used a little lighter bat. He said it was best to have a bat too light than too heavy. That’s when I went down from 34 (ounces) down to about 32.”

Over time, McCovey preferred a heavier bat and long one, extending from 34½ inches to 35, virtually unheard of today.

“When I look back at it, I kind of hate I did that,” he said. “What’s done is done. You’d be amazed how much difference that little half an inch makes. It doesn’t sound like much, but it is. It’s hard to get to that inside pitch. I’ve got long arms anyway, so why do I need a long bat?”

Moment with Stan the Man

McCovey wasn’t much for fraternizing, especially early in his career. There were exceptions such as the spring training chats with Williams.

“When I showed up at the ballpark and went on the field, I had my game face on,” McCovey said. “Willie was just the opposite. He’d be around the cage, giggling and laughing with all the visiting players. Not me. I was a little standoffish.”

Another exception came late in Stan Musial’s career.

“I talked to him one day, actually his last trip to San Francisco as a regular player,” said McCovey, recalling a Giants-Cardinals game at Candlestick Park on Sept. 27, 1962. “He was coming out of the right-field door where the visiting players came out. We were just finishing our batting practice, and they were beginning to start theirs. I stopped him, and he talked to me for a long time, and I think he went out and got five hits that day.”

Indeed, Musial went 5-for-5, and the Cardinals won 7-4.

“He was a very nice guy, Stan,” McCovey said. “He can hit.”

The line drive

Nowadays, defensive shifts are standard. In McCovey’s day, teams didn’t usually shift unless McCovey, who was taught to pull early in his career by Lefty O’Doul, was at the plate.

Not for the final play of the 1962 World Series, however.

With two outs and runners at second and third in the ninth inning of Game 7, McCovey hit a rocket to the right side that was gloved by second baseman Bobby Richardson. The Yankees won 1-0 to clinch the Series.

Based on films of the play, Richardson was playing McCovey straightaway.

“He was playing over toward second base,” McCovey said. “He wasn’t playing me to pull like most second basemen would do. Everybody had those exaggerated shifts against me. Other than Ted Williams, I’m the only one who they had those exaggerated shifts against. But (Richardson) was playing toward the bag, almost like a right-handed hitter was up, really.”

Had Richardson shifted, Giants fans might not have had to wait another 48 years to celebrate a World Series championship.

Willie and the Duke

After Game 7, McCovey ducked into a San Francisco nightclub where Duke Ellington was performing his jazz standard, “I Got It Bad (and That Ain’t Good).”

“The night I lined out, I went to this club,” McCovey said. “I was walking into the club, and Duke changed the lyrics when he saw me to, ‘He hit it good and that ain’t bad.’”

McCovey said he smiled.

One of the all-time pick-me-ups.

McCovey didn’t sulk after ’62. He followed with a breakout year and hit 44 home runs.

“Hank (Aaron) and I, both from Mobile, both wore 44 — I wore 44 because of him — we both ended up hitting 44 home runs to tie for the home run title,” McCovey said. “Quite a big coincidence.”

The mound hardly mattered

McCovey won the MVP award in 1969, hitting .320 while leading the league in homers (45) and RBIs (126). The mound was lowered that year from 15 inches to 10 in an attempt to beef up offenses.

The year before, McCovey also led the league in homers (36) and RBIs (105) while hitting .293. Offensive numbers were historically low throughout the rest of the game — the collective batting average was .237, the ERA 2.98 — but McCovey’s went up considerably from 1967.

“It was just about then that I was really coming into my own,” McCovey said. “All those big superstars had bad years or so-so years, and I had a great year that year. That’s when Willie campaigned for me to be the MVP. They gave it to (Bob) Gibson. They gave Gibson both awards, Cy Young and the MVP. Willie thought I should’ve won the MVP. So the next year, I decided to have a little better year. I said, ‘I’ll show you.’”

He did. And again in 1970 when he led the league in OPS a third straight year.

Explaining the ’60s

The Giants had five Hall of Famers in the ’60s: Mays, McCovey, Orlando Cepeda, Juan Marichal and Gaylord Perry. Statues for each were erected in China Basin. So why did the Giants play in just one World Series in the decade?

McCovey suggested the team always seemed to be a starting pitcher away.

“We had stacked lineups,” McCovey said. “Nothing wrong with our lineup. We only had two good pitchers, it seemed. Marichal-Jack Sanford, Marichal-Gaylord. ...”

In an annoying run filled with what-ifs, the Giants finished second five straight years — three times by three or fewer games. From 1965 to 1968, they were second in the league. In 1969, the first year of division play, they were second in the NL West.

“We were a line drive away from winning in ’62,” McCovey said. “I thought then we were going to win a lot of them. We had such a good team. I think that’s why we weren’t too down on not winning that Series. Because we figured we had such a good team that we were going to win a lot more. Little did I know it wouldn’t happen. There were a lot of very good teams.”

Meeting Jackie

McCovey, who reached the majors 12 years after Jackie Robinson broke the color line, revealed two race-related issues in his career that he was forced to deal with, one early and one late.

First in 1957 while playing for the Double-A Dallas Eagles of the Texas League: “When I was at Dallas, we couldn’t go to Austin. Black players couldn’t play in Austin. We didn’t even make the trip there. Weren’t allowed. We usually played in Houston before we went to Austin, so we’d stay in Houston when the rest of the team went to Austin. Then we met them in the next city.”

McCovey said the racism he experienced in the big leagues was “a little more subtle,” including from hate mail. However, it got to the point in 1980 that the federal government got involved.

“People might not know this,” McCovey said, “but my last year with the Giants, they had an FBI guy follow me on the road everywhere we went because of the threats I had gotten. Naturally, they didn’t tell anybody. They kept it quiet. Just somebody trying to get attention, I think. But they take things like that seriously.”

McCovey said he met Robinson just once, when McCovey was a teenager in Mobile and Robinson’s barnstorming team visited. McCovey’s connection was Alex Pompez, who recommended the teenager to the Giants and was traveling with Jackie.

“Alex made sure to call me and took me down in the clubhouse and introduced me to Jackie,” McCovey said. “It’s funny because during that time, we didn’t think of asking for autographs. Just meeting him and shaking his hand was enough for me.”

The other teams

It’s hard to envision all these years later, McCovey wearing Padres and A’s uniforms in the mid-’70s.

The Padres were owned by fast-food mogul Ray Kroc, and McCovey said, “He used to call me the original Big Mac.”

The A’s owner, of course, was Charlie Finley: “To this day, I can’t figure that out. He just liked stockpiling players. They already had Billy Williams. Ken McMullen was there, Nate Colbert. All those guys were there, why did they need me? Then they wouldn’t use any of us.”

McCovey was sold to the A’s for the final month of 1976 and had five hits in 11 games, never homering in the American League. He rejoined the Giants in 1977, won the NL Comeback Player of the Year award and retired in 1980 at 42.

Thirty-eight years later, on the verge of 80, McCovey continues to receive heaps of love when introduced on the field or simply making his way through the ballpark.

“It’s flattering to still be thought of in that vein when you’ve been retired for so long,” he said. “Sometimes you fade away from the people. At least I haven’t faded away completely.

“When I was growing up, that seemed ancient, to be 80. But I don’t feel any different than when I turned 40, really.”

John Shea is The San Francisco Chronicle’s national baseball writer. Email:jshea@sfchronicle.com Twitter: @JohnSheaHey