The Giants optioned Menez to Triple-A Sacramento on Monday, Alex Pavlovic of NBC Sports Bay Area reports.
San Francisco will need to break in two new back-end rotation members this week after Menez was optioned and Shaun Anderson (finger) was placed on the 10-day injured list. Menez' first two starts in the big leagues were encouraging, but he struggled mightily in Sunday's 9-6 win over the Phillies, lasting just 1.2 innings while ceding three runs on two hits and three walks.