Nationals sign infielder Rosario, designate Adon for assignment

The Nationals signed Amed Rosario to a one-year, $2 million contract this morning, adding an experienced middle infielder who could take over the utilityman role on the 2025 roster.

Rosario, 29, owns a .273 batting average and .706 OPS in 942 career big league games with five clubs, most of those coming with the Mets and Guardians. An everyday shortstop in New York and Cleveland during the first portion of his career, he has shifted into more of a utility role in recent seasons.

Rosario played for three different teams (Rays, Dodgers, Reds) in 2024, finishing with a .280 batting average, .686 OPS, 18 doubles, three homers, 32 RBIs and 13 stolen bases across 346 plate appearances. He played all around the field, with 27 games at second base, 26 in right field, 15 at third base and 14 at shortstop.

To clear space for Rosario on their full 40-man roster, the Nationals designated right-hander Joan Adon for assignment. Adon, who burst onto the scene with a nine-strikeout debut against the Red Sox on the final day of the 2021 season, never rediscovered that magic during the ensuing three years. In 35 total big league games with the Nats (26 of them starts), he went 3-16 with a 6.66 ERA.

Rosario appears poised to take over the utility role previously held by Ildemaro Vargas, who was cut loose in November after 2 1/2 seasons in D.C. Rosario is four years younger than Vargas, with better offensive numbers but less defensive prowess.

The addition of Rosario could quash any realistic possibility of Nasim Nuñez making the Nationals’ Opening Day roster. The Rule 5 draftee impressed in the field and made strides at the plate late during his rookie season, but he’s now free to be optioned to Triple-A without risk of being lost to another organization. The club likely wants him to get more regular playing time, starting at shortstop for Rochester and available for a promotion if anything happens with CJ Abrams.

Less clear is how Rosario’s acquisition impacts José Tena. The 23-year-old rookie finished the season as the Nationals’ starting third baseman, and he could retain that role entering 2025, at least until top prospect Brady House is deemed ready to debut. Tena, though, was also viewed as a potential utility infielder who is better defensively at second base and shortstop than third base, but the addition of Rosario would seem to block him from holding that role.

The Nats have now added five major league players this offseason (Rosario, Nathaniel Lowe, Josh Bell, Michael Soroka, Trevor Williams) at a projected total cost of $34.7 million for the 2025 season. (Lowe and Williams are under team control for 2026 as well, projected to earn a combined $22 million for that season.)

They could still pursue an experienced third baseman, pushing Tena to Triple-A and giving House more time to develop. They also still need to address a bullpen that no longer has top arms Kyle Finnegan, Hunter Harvey, Dylan Floro and Robert Garcia.