Christian Koss is a right-handed third baseman from Riverside, California, who broke into the big leagues on April 1, 2025, with the San Francisco Giants. He was 27 years old at the time — a California kid who worked his way through San Francisco’s minor-league system and earned a shot at the roster as a reliable defensive presence at the hot corner.
Quick Facts
- Full name: Christian Koss
- Position: Third Base
- Team: San Francisco Giants
- Number: 50
- Bats / Throws: Right / Right
- Height / Weight: 6’1″ / 185 lbs
- Born: January 27, 1998 — Riverside, CA 🇺🇸
- MLB Debut: April 1, 2025
Background
Koss grew up in Riverside, California, and developed through the Giants’ farm system, where he built a reputation as a dependable defender at third base. San Francisco called him up in 2025 to shore up the infield, and he wasted no time making the most of his opportunity.
Professional Career
In his 2025 debut season, Koss put together a solid first showing: a .264 batting average, 3 home runs, 23 RBI, 25 runs scored, a .677 OPS, and 4 stolen bases. Not a flashy line, but a respectable one for a first-year player finding his footing in the majors.
2026 brought a tougher stretch. Koss saw his average drop to .211 with 3 home runs, 8 RBI, 20 runs scored, and an OPS of .563 in fewer plate appearances. The numbers reflect the consistency challenges that come with establishing yourself at the big-league level — something many young players work through before breaking through.
Career Stats
- 2025 — SF Giants: .264 AVG | 3 HR | 23 RBI | 25 R | .677 OPS | 4 SB
- 2026 — SF Giants: .211 AVG | 3 HR | 8 RBI | 20 R | .563 OPS | 2 SB
Awards & Milestones
Koss hasn’t collected individual hardware yet — no All-Star nods, Silver Sluggers, or World Series rings. His MLB career is still young, and there’s plenty of runway ahead with San Francisco.
Worth Knowing
Koss is part of a growing wave of California-bred talent pushing through to the majors. His defensive reliability at third base — a position where glove work matters just as much as the bat — has been central to his identity as a player since his minor-league days. The offense is still a work in progress, but the foundation is there.

