Buster Posey, four months into his tenure as San Francisco Giants president of baseball operations, has hired former teammates Santiago Casali and René López to front-office roles focused on player development and organizational infrastructure. Casali, who caught 106 games across three seasons with the Giants through 2022, joins as a special assistant in baseball operations. López, who pitched 48 innings for San Francisco in 2021–2022, takes a development-side role working with minor-league pitchers.

The moves extend a pattern visible since Posey left the field in 2021 and returned to the organization's leadership in November 2024. He has staffed key positions with former players who understand the 162-game grind from the dugout side. Casali and López join a front office that already includes Matt Cain (vice president of player development) and Will Clark (special assistant). The organization now has five former major leaguers in decision-making or advisory roles, a higher ratio than any National League West competitor except the Dodgers.

Posey's roster-building authority begins with the $197 million in commitments already on the books for 2025. The Giants finished 80-82 last season, missing the playoffs for a third consecutive year despite the eighth-highest payroll in baseball. The hiring of Casali and López signals an internal belief that San Francisco's development pipeline—not its free-agent checkbook—needs attention. Casali spent parts of seven seasons in the majors, logging time with Tampa Bay and Cincinnati before his Giants stint. His career .221 batting average and .294 on-base percentage suggest his value to Posey lies in defensive teaching and game-calling nuance, not hitting instruction. López, meanwhile, posted a 4.50 ERA across three organizations before retiring in 2023. His hire points to a focus on mechanical consistency and command development in the lower minors, where San Francisco's pitching prospects have underperformed slot value since 2020.

The front-office additions come as the Giants prepare for a coaching-staff overhaul under new manager Bob Melvin, who was hired in October 2023. Melvin's staff still has two open slots—one bench coach position and one assistant hitting coach role—expected to be filled by mid-January. Casali and López will not wear uniforms but will spend time at the team's Scottsdale, Arizona, spring facility and make periodic visits to the club's six full-season affiliates. Their proximity to Posey matters: both men played for him during his final seasons as a catcher, giving them direct insight into how he evaluates decision-making under pressure.

The Giants have not made a major-league roster addition since signing Jung Hoo Lee to a $113 million deal last December. The current front office's stated priority is re-signing shortstop Willy Adames, who became a free agent in November and is drawing interest from the Dodgers and Braves. Adames is expected to command a deal in the $160–$180 million range over six or seven years. If San Francisco loses him, Posey's in-house development bet becomes more urgent. The organization's top three prospects—Bryce Eldridge, Walker Martin, and Carson Whisenhunt—are all at least 18 months from major-league readiness.

Posey's front-office philosophy appears borrowed from the Giants teams that won three World Series between 2010 and 2014: hire people you trust, limit leaks, prioritize defense and sequencing over raw tools. Casali and López fit the profile. Neither will appear on ESPN. Both know what it takes to catch a playoff game at Oracle Park.

The Giants open spring training on February 14. Casali and López will be in uniform for early workouts, then return to Scottsdale as minor-league camp begins. The team's amateur draft is July 13–15, and the new front-office additions will have input on prep catchers and college relievers. Whether that input translates to wins depends on Posey's ability to convert relationships into development velocity. For now, he is betting on men who already know his signs.