Hellickson (shoulder) announced his retirement from professional baseball Friday, Tommy Birch of The Des Moines Register reports.

Hellickson suffered a shoulder setback and is unlikely to pitch this season, Craig Mish of FNTSY Sports Radio reports.

Hellickson (shoulder) was activated off the 60-day injured list Sunday.

Hellickson (shoulder) tossed two scoreless innings Wednesday in a rehab appearance for the Nationals' rookie-level Gulf Coast League affiliate. He gave up a base hit and struck out two in the 12-pitch outing.

Hellickson (shoulder) is scheduled to throw a simulated game Wednesday, Mark Zuckerman of MASN Sports reports.

Hellickson (shoulder) could throw a simulated game this week, Jesse Dougherty of The Washington Post reports.

Hellickson (shoulder) moved to the 60-day injured list Tuesday, Mark Zuckerman of MASN Sports reports.

Hellickson received a PRP injection Thursday to help alleviate his shoulder pain, Jamal Collier of MLB.com reports.

Hellickson (shoulder) has been shut down from throwing, Jesse Dougherty of The Washington Post reports.

Hellickson's shoulder injury was referred to as tendinitis by manager Dave Martinez on Tuesday, Mark Zuckerman of MASN Sports reports.