D-backs send David Hernandez down

PHOENIX -- The Arizona Diamondbacks have optioned struggling reliever David Hernandez to Triple-A Reno.

Arizona's primary setup man the previous two seasons, Hernandez has struggled most of this season, entering Saturday's game against the New York Mets with a 4-6 record and a 5.32 ERA.

The right-hander had another rough outing against the Mets, allowing two runs on two hits in the eighth inning of the 4-1 loss.

Hernandez was 2-3 with a 2.50 ERA last season and was 5-3 with a 3.38 ERA in 2011, when the Diamondbacks won the NL West title.

He spent the first two years of his major league career with Baltimore, where he began as a starter.