The Nationals designated Jennings for assignment Monday, Mark Zuckerman of MASN Sports reports.

EDGE Analysis

Jennings will cede his 40-man roster spot to waiver pickup Javy Guerra and his spot on the active roster to Tony Sipp (oblique), who was activated from the 10-day injured list. Valued as a lefty specialist for much of his career, Jennings has allowed eight of the 18 left-handed hitters he has faced this season to reach base.