That means Darvish would be waiting in case he's needed for extra innings.
"He's the freshest guy we have, so we designated him as the last guy standing," Washington said. "He's had the most time down than anybody."
Darvish's last start was skipped to give the Japanese right-hander some extra rest through the All-Star break. He hasn't pitched in eight days.
"If we need them, they'll pitch," Washington said.
Washington also revealed his first three pitchers for the contest. Justin Verlander will pitch two innings as the starter, followed by Tampa Bay Rays left-hander David Price and Los Angeles Angels right-hander Jered Weaver for one inning each.
After that, Washington said he will assess the flow of the game and figure out how to line up the rest of the pitchers.