Nationals broadcaster Dan Kolko announced during MASN's broadcast of Sunday's game against the Angels that Parra has elected to retire and will join Washington's front office as a special assistant, Mark Zuckerman of MASNSports.com reports.

Parra signed a minor-league contract with the Nationals on Sunday that includes an invitation to major-league camp, Jesse Dougherty of The Washington Post reports.

Parra (knee) was activated off the injured list Saturday, Jessica Camerato of MLB.com reports.

Parra was placed on the 10-day injured list Sunday with right knee inflammation, Jessica Camerato of MLB.com reports.

Parra went 0-for-2 with a hit by pitch, a stolen base and a run scored in Friday's 8-4 loss to Atlanta.

Parra is out of the lineup for Sunday's game against the Cubs.

Parra isn't starting Saturday's game against the Cubs, Matt Weyrich of NBC Sports Washington reports.

Parra is out of the lineup for Sunday's game against the Orioles, Jessica Camerato of MLB.com reports.

Parra went 3-for-5 with a double, two runs scored and an RBI in Monday's rout of the Marlins.

The Nationals selected Parra's contract from Triple-A Rochester on Sunday.