Peguero was designated for assignment last week by the Giants, who missed the playoffs this year after winning their second World Series championship in three seasons in 2012.
Peguero has played 35 games in the majors the past two seasons, batting .200 with one home run and one RBI.
Rosario went 3-2 with a 3.02 ERA in 43 appearances for San Francisco.
- Sports & Recreation
- San Francisco Giants
- Francisco Peguero