After missing the last three games versus New York, Walker met with a specialist on Friday morning and decided to shut it down for the season.
Walker, a four-year veteran, has 14 home runs and 69 RBIs while hitting .280 in 129 games for the Pirates this season. Josh Harrison made the start at second base in Walker's absence in the last three games versus New York. Harrison has three home runs and 16 RBIs and is hitting .238 in 99 appearances with the Pirates this season.
The Pirates are currently fourth in the National League Central with a record of 76-80 and will close out the regular season at home with three games each versus the Cincinnati Reds and Atlanta Braves, both of whom have qualified for the playoffs.