Mike Trout
On April 17, 2015, Trout became the youngest player in MLB history to reach 100 home runs and 100 stolen bases. He was 23 years and 253 days old when he reached the milestone, passing the previous record-holder, Alex Rodriguez, who had achieved it at the age of 23 years and 309 days in 1999. Trout led off the 2015 MLB All-Star Game with a home run, becoming the fourth player in All-Star Game history to do so. For the second year in a row, Trout won the All-Star Game MVP Award, becoming the first player ever to win it in consecutive years. On September 22, Trout hit his 40th home run, becoming only the second Angels player to hit 40 home runs in a season. Trout led the AL in WAR for the fourth straight year.
Lew Malone
Lewis Aloysius Malone (March 13, 1897 – February 17, 1972) was an American professional baseball infielder. He played in Major League Baseball (MLB) from 1915 to 1919 for the Philadelphia Athletics and Brooklyn Robins. In 1918 Malone's career was interrupted while he served in World War I. After returning from World War I, Malone continued to play in the Minors until 1929.
His first (and last) major league home run came in 1915, at the age of 18. He is believed to be the youngest major leaguer ever to hit his last home run.