Giants Claim Justin Dean and Reiver Sanmartin to Boost Roster

The San Francisco Giants made notable moves on Thursday, claiming outfielder Justin Dean from the Los Angeles Dodgers and left-handed pitcher Reiver Sanmartin from the Cincinnati Reds, as reported by MLB.com. In a corresponding move, right-hander Mason Black was designated for assignment to open a spot on the 40-man roster. Dean, 28, had a limited role with the World Series-winning Dodgers this season, appearing in just 18 regular-season games. Despite his small sample of at-bats, Dean’s elite defense and speed earned him a spot on the Dodgers’ postseason roster. He was involved in a critical moment during Game 6 of the World Series against the Toronto Blue Jays: his awareness in signaling for a dead-ball ruling after a ninth-inning double prevented Toronto from scoring, ultimately allowing the Dodgers to force a Game 7. The Dodgers went on to become the first team since the New York Yankees (1998-2000) to win consecutive championships. Although Dean did not record a plate appearance during the postseason, he was used 13 times as a defensive replacement. His Triple-A performance for Oklahoma City was strong, hitting .289 with an .809 OPS, six home runs, and 27 stolen bases over 90 games. This combination of speed and defense makes him a valuable depth option for the Giants’ outfield, which currently features Heliot Ramos and Jung Hoo Lee as projected starters. Dean, who bats right-handed, will likely compete for regular at-bats alongside prospects such as Drew Gilbert, Luis Matos, and Jerar Encarnacion. Reiver Sanmartin, 29, brings additional pitching depth to San Francisco. Over four seasons with Cincinnati, the Colombian left-hander posted a 5.66 ERA in 62 appearances (including six starts). After undergoing Tommy John surgery in July 2023, Sanmartin returned to the Reds late in the season, allowing only one unearned run in his lone MLB appearance of 2025. At Triple-A Louisville, he impressed with a 2.67 ERA and 55 strikeouts in 67 1/3 innings. With the Giants looking to bolster their bullpen, Sanmartin will join Erik Miller, Joey Lucchesi, and Matt Gage as left-handed options for the 40-man roster. Mason Black, a third-round pick in 2021, struggled with a 6.47 ERA across 10 appearances (eight starts) for the Giants over the last two seasons and a 5.81 ERA in 30 games at Triple-A Sacramento in 2025. His removal from the roster clears the way for fresh talent as San Francisco looks to improve its pitching staff. For a deeper look at Justin Dean’s career stats and recent news, visit his ESPN player profile or follow updates on the official MLB.com player page.