How a 5-foot-10, 235-pound slugger is turning heads as one of the best base-stealers in baseball

Josh Naylor doesn’t look like a baserunning threat. Standing at 5-foot-10 and weighing 235 pounds, the Seattle Mariners’ first baseman has a physique that suggests more power than speed. Yet, since joining the team earlier this season, Naylor has become one of the most effective base-stealers in the league, defying all expectations.

According to Statcast data, Naylor ranks in the second percentile in sprint speed, making him one of the slowest players in the majors. But his success on the basepaths—28 stolen bases in 30 attempts this season—has been nothing short of remarkable. Since joining the Mariners on July 24, he has been perfect on 17 of 17 attempts, going 17 for 17. His ability to read the game and time his steals with precision has made him an unlikely but essential piece of Seattle’s playoff push.

Naylor’s intelligence and instincts have been key to his success. Scouts and front-office executives quickly recognized his ability to anticipate plays and make decisions on the fly. His father instilled in him the value of observing the game, a trait that has translated into an almost extrasensory understanding of when to steal a base.

While speed is often associated with base stealing, Naylor’s story highlights that timing, strategy, and fearlessness are equally important. His success has not only elevated his own career but has also contributed significantly to the Mariners’ resurgence as a championship contender. With the team on the verge of its first division title since 2001, Naylor’s impact on the field is undeniable.

Naylor’s achievements have also set a new precedent in baseball history. According to data from Baseball-Reference, no player under 6 feet and weighing at least 235 pounds had ever swiped more than 10 bases in a season before. Naylor is now closing in on 30, making him one of the most unique and unlikeliest base-stealing success stories in the sport’s history.

Seattle Mariners president of baseball operations Jerry Dipoto described Naylor as “one of the smartest baseball players that I’ve ever been around,” and his teammates have echoed that sentiment. First base coach Eric Young Jr. noted that Naylor is always thinking “three moves ahead,” a trait that has made him a standout in high-pressure situations.

Naylor’s fearlessness on the basepaths has also inspired his teammates. A player of his size being caught could easily draw derision, but Naylor appears entirely unconcerned. “He’s just not afraid to try,” Dipoto said. “What holds guys back in the baserunning area is just fear.”

With the Mariners now in line for their first division title since 2001, Naylor has become a key figure in the team’s historic playoff push. His ability to steal bases and contribute offensively—bolstered by a .292 batting average this season—has made him a valuable asset to a team that is now considered one of the top contenders for the World Series.

As the regular season comes to a close, Naylor’s legacy as one of the most intelligent and strategic base-stealers in the game continues to grow. His journey from a power hitter with no reputation for speed to a baserunning legend is a testament to the value of preparation, intelligence, and courage in modern baseball.