BOSTON -- Mike Yastrzemski stepped up to the plate at Fenway Park where his grandfather, Carl, had belted 237 homers over his 23-year historic career.

Amid the loud ovations in the stands, a fan repeatedly yelled out to the Giants’ leadoff batter, “Hit a home run! Hit a home run!”

Three innings later, Mike did just that.

The 29-year-old rookie’s 20th home run of the season sailed 401 feet over the center-field wall, according to Statcast, off Boston starter Nathan Eovaldi. The crowd reacted not as if the home run had been hit by the opponent, but rather by family. Red Sox history family.

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“That was kind of one of those things where I just had to take a second and understand what was going on and appreciate that moment and not take it for granted,” Mike said after the Giants’ 7-6, 15-inning win over the Red Sox. “I made sure to kind of keep my head up and look around and soak it all in because you don’t really get an ovation at an away or opposing park for your home run.”

Before the game, the grandfather and grandson reunited on the field, an image that transcends generations.

Fenway Park was home for Carl, who played his entire career for the Red Sox, and a homecoming for Mike, who grew up in the Boston area. At that time, neither knew Mike would be making his mark in the stadium 36 years, one month and 17 days after Carl hit his last home run there on July 31, 1983.

“I think the only way that I can compare it to anything would be if I compared it to the '67 season,” Carl said of Mike playing at Fenway before the game. “That’s what it means to me and being here. It’ll be the first time that ‘Yastrzemski’ will be announced on the field since '83.”

Their last name resonated over the loudspeaker from 1961-83. During that time, Carl captured the American League Most Valuable Player Award and Triple Crown for that memorable '67 season, seven Gold Glove Awards and 18 All-Star selections.

“When I turned 23, kind of the big shocking moment was that for my entire life, he had showed up to Fenway Park every day,” said Mike, who went 2-for-7 with a double, a home run, three strikeouts and a walk on the night. “That kind of blew my mind, where I was like, ‘I can’t picture 23 years' worth of Major League Baseball experience.’ That’s when that really set in. But I was probably in high school when I started to see the magnitude of his effect on the city.”

On Tuesday in the series opener, the name was heard once again when Mike got the start in left field -- where Carl played, too.

“It had to be a great night for a lot of Red Sox fans to see a Yastrzemski out there,” Giants manager Bruce Bochy said. “I’m sure it reminded them of some of the great memories they have. It was pretty cool.”

Even the opponents recognized the significance of the moment. Eovaldi heard the loud ovation for Yastrzemski’s home run from the pitcher’s mound.

"He had a good eye at the plate. I fell behind on that 3-1 count, and he was able to drive the ball out of the park," Eovaldi said, adding, "You see our fans, too. They gave him a really good welcoming and everything to come here, and it’s cool. A cool experience for him.”

Batting leadoff and starting at Fenway Park was not given to Mike because of his family. He’s had to work to get to this point on his own. The 29-year-old logged 703 Minor League games before making his Major League debut on May 25. Mike, Carl said, “never complained.”

“I think the whole thing is when you first come to the big leagues, it’s very difficult,” Carl said. “I knew it was for me because always in the back of my mind was the thought that, ‘Do I belong here?’ I think that goes on for a few months until you kind of get settled and say, ‘Yes I do belong here.’ He’s adjusted pretty well to it.”

Since being traded to the Giants from the Orioles in March, Mike has embraced the opportunity. Carl remembers receiving a phone call from his grandson four days after joining his new organization and sensing it would be a good fit. Mike became the first Giants rookie to belt 20-plus home runs since Dave Kingman did it in 1972. He is batting .266 on the season with 89 hits and 52 RBIs.

“You could tell that was a big one for him,” Bochy said. “It was No. 20, but to hit it here, he was on Cloud Nine there.”

Yastrzemski nearly sent another home run to the same location in the 14th inning, but his 408-foot ground-rule double off Brian Johnson fell just short of leaving the park. He stumbled awkwardly getting out of the box after the swing, but stayed in the game after being attended to by Giants staff once he reached second base.

“I’m good,” Mike said. “I just kind of jammed my ankle a little bit, so I’m alright.”

Mike has had his grandfather to turn to during this long journey. Carl watches Mike’s games on the West Coast, even if it means staying up far past midnight.

“He’s helped me a lot through the way in helping me understand what I need to do and what I don’t need to do to be successful and how I can kind of maintain that,” Mike said.

Mike wasn’t the only member of the visiting team that Carl spent time with on Tuesday. Carl visited the clubhouse before the game and dropped into Bochy’s office.

“A Hall of Famer that I grew up trying to impersonate as a hitter, as a kid, and there he was in my office,” Bochy said. “That’s a cool moment. To get a chance to meet him, I’m like anybody that grew up idolizing these guys. ... The beautiful thing about this game is, it does allow you to have moments like this.”

This moment wasn’t just for Mike -- it was for all of his friends and family who came to Fenway Park to see him play there for the first time. There were so many supporters on hand, he lost count. The self-described diehard Red Sox fan said his first game at Fenway Park had been circled on his calendar “for life.”

“I got to walk in here by myself when I got to the field,” he said. “There was a lot of memories of being in the stands. Being in the stands for the World Series, being in the stands for the '99 Home Run Derby, the All-Star Game, being with family at games. Those things overwhelm you more than actually playing here. The playing here is cool and I see it as part of my job, something I’ve always wanted to do. So that doesn’t really overwhelm me. But being able to do it in a setting where I have so many fond memories with friends, family, and then having them be able to be here is special.”

On Tuesday night, and into Wednesday morning, those at Fenway Park experienced the special moment, too.

“The crowd reactions all night were incredible,” Mike said. “I can’t thank them enough for being supportive and showing me some love when I’m on the opposing team. It’s unheard of, and it was really special.”