Justin Upton homered a few days before his 20th birthday in 2007.
In MLB, that was Derek Jeter of the Yankees who hit a home run in the 6th inning of Game 6 of the 2000 World Series.
Tony Conigliaro (born January 7, 1945) of the Boston Red Sox was 19 when he hit 24 home runs in the 1964 season. He is the only MLB player to have hit 20+ HRs in a season while a teenager.
Babe Ruth played 2,503 games in MLB and hit his 714th and last home run in his 2,498th game.
Not in MLB ... although he did hit his first MLB home run in his 3rd ever at bat ... it was a grand slam.
September 6, 1985 off of Derek Botelho of the Cubs at Wrigley Field. It was the 160th home run of his MLB career.
In MLB, Carlos Quentin with 58. Through games played on June 27, 2009 Quentin, currently playing for the Chicago White Sox, has hit the most career home runs of any MLB player whose last name begins with Q. He has also hit the most home runs in a season for any MLB player whose last name begins with Q, having hit 36 HRs in the 2008 season. Mark Quinn of the Kansas City Royals (1999-2002) is second all time with 45.
No, he hit a walk off home run in his first major league game but it was not his first at-bat.
Miguel Cabrera in the 2012 MLB world series
Hank Aaron's final MLB home run came on July 20, 1976 off of Dick Drago of the California Angels.
In MLB, that was Babe Ruth who hit his 600th home run in the 1931 season.
In MLB, that was Babe Ruth who hit 54 home runs in 1920.
Ernie White He hit 144 home runs in mlb history.