Hernandez was injured in a collision at first base with the Cubs' Anthony Rizzo in the seventh inning of Sunday's game (video below), dislocating his left thumb and suffering ligament damage in the thumb as well.
The 25-year-old will have surgery on Wednesday to repair the ligament damage. The estimated recovery time for this type of surgery is usually around three months, so Hernandez should be fine for next season.
The Phillies have brought up infielder Chase d'Arnaud for depth in the absence of Hernandez, but the bulk of the work at second base is expected to go to Darnell Sweeney and Andres Blanco.
Sweeney, who was acquired in the trade that sent Chase Utley to the Dodgers, has hit .200 with three home runs and 10 RBIs in 50 at-bats (59 plate appearances) this season.
The veteran Blanco is batting .301 with an .883 OPS, 18 doubles, five home runs and 19 RBIs in 183 at-bats in 2015.
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