Christopher John Flexen Bio
Christopher John Flexen (born July 1, 1994) is an American professional baseball pitcher who has played across Major League Baseball and the KBO League. Nicknamed “Flex” for excelling in both football and baseball during high school, Flexen has established himself as a versatile pitcher capable of both starting and relieving roles throughout his professional career. He has contributed to multiple MLB organizations and returned to the KBO League with the Doosan Bears, where he previously played during the 2020 season.
Early Life and Background
Flexen was born in Newark, California, and attended Newark Memorial High School in his hometown. At Newark Memorial, he was a dual-sport athlete, serving as the quarterback of the school’s football team while also making the varsity baseball team as a freshman. His outstanding ability in two sports led to his nickname “Flex.” This athletic versatility demonstrated the competitive drive and hand-eye coordination that would later serve him well as a professional pitcher.
Flexen initially committed to continue his baseball career at Arizona State University, joining the Sun Devils program. However, his professional trajectory changed when he was selected in the 2012 MLB Draft. The New York Mets chose Flexen in the 14th round, and he was lured away from his college commitment by a $375,000 signing bonus.
Path to Professional Baseball
After signing with the Mets, Flexen began his professional career in the minor leagues. In 2012, he pitched for the Kingsport Mets in the Appalachian League, posting a 1-3 win-loss record with a 5.63 earned run average in seven games. He returned to Kingsport for the 2013 season and showed significant improvement, compiling an 8-1 record with a 2.09 ERA in 11 starts. The following year, Flexen played for the Savannah Sand Gnats, where he went 3-5 with a 4.83 ERA in 13 starts.
Unfortunately, his development was interrupted when he underwent Tommy John surgery in 2014, a common elbow reconstruction procedure for pitchers. After recovering, Flexen split the 2015 season between Savannah, the Brooklyn Cyclones, and the Gulf Coast League Mets, combining for a 2.42 ERA across 12 games. In 2016, he made a strong comeback with the St. Lucie Mets, recording a 10-9 record with a 3.56 ERA in 25 starts. His performance earned him a spot on the Mets’ 40-man roster after the season.
Christopher John Flexen Career
Early MLB Career with New York Mets (2017–2019)
Flexen began the 2017 season with St. Lucie and dominated the competition, posting a 2.13 ERA while striking out over a batter per inning in just three starts. He earned a promotion to the Binghamton Rumble Ponies on May 31, 2017. On July 27, 2017, Flexen made his MLB debut with the New York Mets, taking the mound against the San Diego Padres at Petco Park. In that start, he gave up four runs on five hits. Notably, he became the fifth Mets player in franchise history to allow a home run to the first batter he faced, surrendering one to Manuel Margot on only his third pitch.
Flexen recorded his first major league win on August 8, 2017, against the Texas Rangers at Citi Field. He pitched 5 and one-third innings, allowed three earned runs, and struck out four batters. MLB.com ranked Flexen as New York’s ninth-best prospect entering the 2018 season. He received another call-up to the majors on May 19, 2018, but struggled in limited action, posting a 12.79 ERA in four appearances. His season ended early when he underwent knee surgery in early August.
KBO Comeback with Doosan Bears (2020)
After being designated for assignment by the Mets in December 2019, Flexen signed with the Doosan Bears of the KBO League on December 7, 2019. The Bears were the reigning Korean Series champions at the time. Flexen excelled in his single season with Doosan, pitching to a 3.01 ERA with 10.2 strikeouts per nine innings. His performance in Korea demonstrated his ability to adapt to international baseball and reminded MLB teams of his potential as a starting pitcher.
Seattle Mariners Breakthrough (2021–2023)
Flexen’s career resurged when he signed a two-year, $4.75 million contract with the Seattle Mariners on December 9, 2020. He made the starting rotation to begin the 2021 season and delivered a breakout performance. On April 3, 2021, he made his first start of the year against the San Francisco Giants, pitching five scoreless innings, allowing four hits and two walks, striking out six batters, and earning the win.
His 2021 season represented a marked improvement from his past performances. Among qualified American League pitchers that year, Flexen finished in the top 10 in ERA (3.61), wins (14), ERA+ (111), Fielding Independent Pitching (3.89), and games started (31). He also recorded the most starts of seven innings pitched with one earned run or fewer allowed among all AL pitchers. Over the course of the season, he attempted pickoffs at first base 141 times, more than any other major league pitcher, though he successfully picked off only three runners.
In 2022, Flexen began the season as a starter before transitioning to a relief role. On August 30, 2022, he recorded his first career save, allowing three runs on five hits in a 9-3 victory over the Detroit Tigers. He finished the season with 33 appearances, an 8-9 record, a 3.73 ERA, 95 strikeouts, and two saves across 137 and two-thirds innings pitched.
During 2023, Flexen made 17 appearances for Seattle (including four starts) and struggled significantly, going 0-4 with a 7.71 ERA in 42 innings. On June 27, 2023, the Mariners designated him for assignment. He was traded to the New York Mets on July 3, 2013, but was designated for assignment without making an appearance and was released on July 6.
Colorado Rockies (2023)
Flexen signed a minor league contract with the Colorado Rockies on July 13, 2023. After two starts for the Triple-A Albuquerque Isotopes, his contract was selected to Colorado’s major league roster on July 29. Over 12 starts with the Rockies, Flexen pitched to a 2-4 record with a 6.27 ERA and 45 strikeouts in 60 and one-third innings. He declared free agency on November 2, 2023.
Chicago White Sox (2024)
On December 30, 2023, Flexen signed a one-year, $1.75 million contract with the Chicago White Sox. In 33 appearances (30 starts) during the 2024 campaign, he compiled a 3-15 record and 4.95 ERA with 123 strikeouts across 160 innings pitched. Despite the challenging win-loss record reflecting the team’s struggles, Flexen showed durability by logging significant innings throughout the season.
Chicago Cubs (2025)
On February 17, 2025, Flexen signed a minor league contract with the Chicago Cubs. He began the season with the Triple-A Iowa Cubs and posted outstanding numbers, going 3-0 with a 1.16 ERA and 21 strikeouts over his first five starts. On April 30, the Cubs selected his contract, adding him to their active roster. On May 2, Flexen earned a save in his first game with the Cubs, pitching three innings and recording four strikeouts in a 10-0 win against the Milwaukee Brewers. In 21 appearances for Chicago, he compiled a 5-1 record and 3.09 ERA with 22 strikeouts across 43 and two-thirds innings pitched. The Cubs designated Flexen for assignment on July 29, and he was released after clearing waivers on August 3.
Return to Doosan Bears (2025–Present)
Following his release from the Cubs, Flexen signed a one-year, $1 million contract to return to the Doosan Bears on December 18, 2025. This marked his second stint with the KBO club, where he previously excelled during the 2020 season. Flexen continues to serve as a valuable rotation piece for the Bears as they pursue another Korean Series championship.
Flexen’s Pitching Profile
Flexen has developed into a crafty pitcher who relies on location and pitch sequencing rather than overpowering velocity. His ability to work multiple innings and pitch effectively in various roles has extended his career across multiple organizations and leagues. Throughout his career, he has demonstrated resilience, recovering from Tommy John surgery and multiple team transitions to remain a productive professional pitcher.
Christopher John Flexen Career Wins
Flexen has accumulated wins across both Major League Baseball and the KBO League throughout his professional career. His MLB career spans seven seasons with five different franchises, while his KBO experience has provided additional victories with the Doosan Bears. His career reflects consistency and adaptability across different baseball environments.
MLB Career Highlights
Flexen’s MLB career includes a 35-50 win-loss record with a 4.83 ERA and 488 strikeouts across his time with the Mets, Mariners, Rockies, White Sox, and Cubs. His 2021 season with Seattle stands out as his most successful, as he earned 14 wins while maintaining a 3.61 ERA. His first career save came with the Mariners in August 2022 against the Detroit Tigers. His most recent MLB save came in May 2025 with the Cubs against Milwaukee.
KBO and Career Summary
In his KBO career with the Doosan Bears, Flexen has posted an 8-5 record with a 3.06 ERA and 135 strikeouts through March 30, 2026. His combined professional statistics reflect a pitcher who has successfully navigated the transition between American and Korean baseball, demonstrating adaptability and consistent performance across different leagues and competition levels.
| League | Wins | Losses | ERA | Strikeouts |
|---|---|---|---|---|
| MLB (Career) | 35 | 50 | 4.83 | 488 |
| KBO (Career) | 8 | 5 | 3.06 | 135 |
2025 Season Performance
Flexen’s 2025 season represented a tale of two leagues. He began the year in the Chicago Cubs organization, performing exceptionally well at the Triple-A level with the Iowa Cubs before earning a promotion to the majors in late April. His debut with the Cubs was memorable, as he recorded a save while pitching three scoreless innings against the Milwaukee Brewers. Throughout his time with Chicago, Flexen showed the versatility to pitch in relief and contribute positively to the bullpen.
After being designated for assignment and released by the Cubs in late July, Flexen quickly found a new opportunity. He signed with the Doosan Bears in December 2025, returning to the KBO League where he had previously found success. This move allowed him to continue his professional career in a league where he had already demonstrated his abilities. His one-year, $1 million contract reflects the Bears’ confidence in his performance.