Christian Koss (born January 27, 1998) is an American professional

baseball Baseball is a bat-and-ball games, bat-and-ball sport played between two team sport, teams of nine players each, taking turns batting (baseball), batting and Fielding (baseball), fielding. The game occurs over the course of several Pitch ...

infielder An infielder is a baseball player stationed at one of four defensive "infield" positions on the baseball field, between first base and third base. Standard arrangement of positions In a game of baseball, two teams of nine players take turns pla ...

for the

San Francisco Giants The San Francisco Giants are an American professional baseball team based in San Francisco. The Giants compete in Major League Baseball (MLB) as a member club of the National League (baseball), National League (NL) National League West, West Div ...

Major League Baseball Major League Baseball (MLB) is a professional baseball league composed of 30 teams, divided equally between the National League (baseball), National League (NL) and the American League (AL), with 29 in the United States and 1 in Canada. MLB i ...

(MLB). He made his MLB debut in 2025.

Early life

Koss was born and grew up in

Riverside, California Riverside is a city in and the county seat of Riverside County, California, United States. It is named for its location beside the Santa Ana River. As of the 2020 census, the city has a population of 314,998. It is the most populous city in th ...

, and attended

John W. North High School John W. North High School is a public high school in Riverside, California, part of the Riverside Unified School District, and the home of the Huskies. It is an International Baccalaureate school. History John Wesley North High School was establ ...

. Koss attended the

University of California, Irvine The University of California, Irvine (UCI or UC Irvine) is a Public university, public Land-grant university, land-grant research university in Irvine, California, United States. One of the ten campuses of the University of California system, U ...

, and played

college baseball College baseball is baseball that is played by Student athlete, student-athletes at institutions of higher education. In the United States, college baseball is sanctioned mainly by the National Collegiate Athletic Association (NCAA); in Japan, ...

for the

UC Irvine Anteaters The UC Irvine Anteaters are the athletic teams fielded by the University of California, Irvine (UC Irvine). Its athletics programs participate in the NCAA's Division I, as members of the Big West Conference and the Mountain Pacific Sports Feder ...

for three seasons. Following his freshman and sophomore seasons, he played

collegiate summer baseball Collegiate summer baseball leagues are amateur baseball leagues in the United States and Canada featuring players who have attended at least one year of college and have at least one year of athletic eligibility remaining. Generally, they operat ...

with the

Yarmouth–Dennis Red Sox The Yarmouth–Dennis Red Sox, or Y-D Red Sox, are a collegiate summer baseball team based in South Yarmouth, Massachusetts. The team is a member of the Cape Cod Baseball League (CCBL) and plays in the league's East Division. The Red Sox play th ...

of the

Cape Cod Baseball League The Cape Cod Baseball League (CCBL or Cape League) is a collegiate summer baseball wooden bat league located on Cape Cod in the U.S. state of Massachusetts. One of the nation's premier collegiate summer leagues, the league boasts over 1,000 forme ...

and was named a league All-Star in 2018. Koss batted .307 with five home runs and 30 RBI in 54 games as a junior.

Professional career

Colorado Rockies

Koss was drafted by the

Colorado Rockies The Colorado Rockies are an American professional baseball team based in Denver. The Rockies compete in Major League Baseball (MLB) as a member club of the National League (baseball), National League (NL) National League West, West Division. Th ...

in the 12th round, with the 369th overall selection, of the

2019 Major League Baseball draft The 2019 Major League Baseball draft was held from June 3 to 5, 2019. The draft assigned amateur baseball players to MLB teams. The draft order was set based on the reverse order of the 2018 MLB season standings. In addition, compensation picks ...

. He was subsequently assigned to the rookie-level

Grand Junction Rockies The Grand Junction Jackalopes are an independent baseball team of the Pioneer League, which is not affiliated with Major League Baseball (MLB) but is an MLB Partner League. They are located in Grand Junction, Colorado, and play their home games ...

, where he batted .332 with 11 home runs, 11 doubles, four triples, and 51 RBI. Koss did not play in a game in 2020 due to the cancellation of the minor league season because of the

COVID-19 pandemic The COVID-19 pandemic (also known as the coronavirus pandemic and COVID pandemic), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began with an disease outbreak, outbreak of COVID-19 in Wuhan, China, in December ...

Boston Red Sox

On December 4, 2020, Koss was traded to the

Boston Red Sox The Boston Red Sox are an American professional baseball team based in Boston. The Red Sox compete in Major League Baseball (MLB) as a member club of the American League (AL) American League East, East Division. Founded in as one of the Ameri ...

in exchange for Yoan Aybar. Koss spent the 2021 season with the

High-A High-A, officially Class High-A, formerly known as Class A-Advanced, and sometimes abbreviated "A+" in writing, is the third-highest level of play in Minor League Baseball in the United States and Canada, below Triple-A (baseball), Triple-A and D ...

Greenville Drive The Greenville Drive are a Minor League Baseball team based in Greenville, South Carolina. They are the High-A affiliate of the Boston Red Sox and are a member of the South Atlantic League. They play their home games at Fluor Field at the West E ...

and batted .271/.325/.451 with 15 home runs, 55 RBI, and 10 stolen bases across 104 games. Koss was named to the Red Sox' 2022

spring training Spring training, also called spring camp, is the preseason of the Summer Professional Baseball Leagues, such as Major League Baseball (MLB), and it is a series of practices and exhibition games preceding the start of the regular season. Spri ...

roster as a non-roster invitee. He began the season in Double-A with the

Portland Sea Dogs The Portland Sea Dogs are a Minor League Baseball team based in Portland, Maine, playing in the Eastern League (1938–present), Eastern League. Established in 1994, the Sea Dogs are the Double-A (baseball), Double-A affiliate of the Boston Red ...

. For the year, he played 125 total games for Portland, batting .260 with 17 home runs and 84 RBI. In 2023, Koss split time between Portland, the Triple-A

Worcester Red Sox The Worcester Red Sox (nicknamed the WooSox) are a professional minor league baseball team based in Worcester, Massachusetts. Beginning play in 2021, the team is the Triple-A affiliate of the Boston Red Sox, succeeding the Pawtucket Red Sox. Th ...

, and the rookie-level

Florida Complex League Red Sox The Florida Complex League Red Sox are a professional baseball team competing in the rookie-level Florida Complex League (FCL) of Minor League Baseball. The team is owned and operated by the Boston Red Sox of Major League Baseball (MLB). Prior t ...

, batting a combined .235 with four home runs and 23 RBI in 79 games.

San Francisco Giants

On March 27, 2024, Koss was traded to the

organization. He split the year between the rookie-level

Arizona Complex League Giants The Arizona Complex League Giants are a professional baseball team competing as a Rookie-level affiliate of the San Francisco Giants in the Arizona Complex League of Minor League Baseball. The team plays its home games at Scottsdale Stadium in Sc ...

, Double-A

Richmond Flying Squirrels The Richmond Flying Squirrels are a Minor League Baseball team based in Richmond, Virginia. The team, which is a part of the Eastern League, is the Double-A affiliate of the San Francisco Giants major league club, and plays at The Diamond. Th ...

, and Triple-A

Sacramento River Cats The Sacramento River Cats are a Minor League Baseball team of the Pacific Coast League (PCL) and are the Triple-A (baseball), Triple-A affiliate of the San Francisco Giants. Prior to 2015, the River Cats were the Triple-A affiliate of the Oakland ...

. In 88 appearances for the three affiliates, Koss batted a combined .299/.376/.496 with nine home runs, 47 RBI, and 13 stolen bases. On March 26, 2025, the Giants selected Koss' contract after he made the team's

Opening Day Opening Day is the day on which professional baseball leagues begin their regular season. For Major League Baseball (MLB) and most of the American minor leagues, this day typically falls during the first week of April, although in recent year ...

roster. On April 27, Koss recorded his first MLB

run batted in A run batted in or runs batted in (RBI) is a statistic in baseball and softball that credits a batter for making a play that allows a run to be scored (except in certain situations such as when an error is made on the play). For example, if th ...

with a single off of Texas Rangers reliever Jacob Latz, which scored

Heliot Ramos Heliot Lemuel Ramos Lebrón (pronounced "''Eliot''"; born September 7, 1999) is a Puerto Rican professional baseball outfielder for the San Francisco Giants of Major League Baseball (MLB). The Giants selected Ramos in the first round, with the 1 ...

. On May 13, Koss hit a go-ahead grand slam in the second inning of a game against the

Arizona Diamondbacks The Arizona Diamondbacks are an American professional baseball team based in Phoenix, Arizona. The Diamondbacks compete in Major League Baseball (MLB) as a member club of the National League (NL) West Division. The franchise was established ...

. The hit, off of Brandon Pfaadt, was Koss' first career home run.

References

External links

UC Irvine Anteaters bio
{{DEFAULTSORT:Koss, Christian 1998 births Living people Águilas Cibaeñas players Arizona Complex League Giants players Baseball players from Riverside, California Criollos de Caguas players Florida Complex League Red Sox players Grand Junction Rockies players Greenville Drive players John W. North High School alumni Major League Baseball infielders Portland Sea Dogs players Richmond Flying Squirrels players Sacramento River Cats players San Francisco Giants players Scottsdale Scorpions players UC Irvine Anteaters baseball players Worcester Red Sox players Yakima Valley Pippins players Yarmouth–Dennis Red Sox players