Hu has appeared in 96 games over the course of four seasons with the Dodgers, but has not seen regular big league playing time since 2008. Before that season, Baseball America ranked the middle infielder 55th among big league prospects, but he has yet to produce much in the majors.
Hu, who turns 27 in February, posted a .317/.339/.438 line in 223 plate apperarances at Triple-A last year. It seems likely that he'll compete with the likes of Brad Emaus, Luis Hernandez and Ruben Tejada for a job this spring.
Antonini, 25, started 25 games at the highest levels of the Mets organization last year, logging 168 1/3 innings and posting a 4.49 ERA. He limited walks (1.7 BB/9) and posted relatively strong strikeout numbers (7.0 K/9), as he has done throughout his four-year minor league career.