And Shawn Kelley, who inherited Robertson's duties on Monday, is not available to Joe Girardi tonight after having worked in three of the past four games, including taking the loss in last night's 5-4 defeat by the Orioles.
A possible replacement for Kelley, Adam Warren, is also not available tonight for the same reason -- three games in the past four nights.
Joe Girardi will have some decisions to make tonight.
So who gets the call if there's a lead to be protected in the top of the ninth tonight?
"We'll have to see where we are tonight," Girardi said.
Meaning, the manager is likely to mix and match along lefty-righty lines. Possible candidates are Matt Thornton, a lefty, Dellin Betances and Shane Greene, both hard-throwing righties, and Cesar Cabral, another lefty who was recalled earlier this week when Robertson went down.
And Girardi said as much as he would like to be able to save Thornton -- the most experienced of the four -- for that spot, he might be needed earlier in the game if a Boston lefty like David Ortiz comes up in a critical at-bat.
"You could have a situation that is a turning point in the game," Girardi said. "So as much as you'd like to save [Thornton] you have to see where we're at in the game and who's hitting."
The way the manager uses his bullpen tonight could determine whether the Yankees start out those 19 games against Boston with a win or a loss.
Roberts sits:Dean Anna is making his first Yankee Stadium start tonight at second base, meaning Brian Roberts is taking a seat for the first time this season. But not to worry: The 36-year-old Roberts, who has a history of injury, is fine.
“Brian’s played in every game," Girardi said. "He was on pace to play 162. So I thought I would give him a day off.”
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Joe says McCann can:Brian McCann has gotten off to a slow start as a Yankee, going 0-for-12 in the three games against the Orioles and hitting .152 with no home runs and just two RBIs. But Girardi said he is not worried about his catcher adjusting to being a Yankee, not even with a high-pressure Red Sox series this weekend.
"I don't think that he's swung the bat as poorly as his numbers have said," Girardi said. "But sometimes you run into some hard luck. He hit two balls on the screws yesterday and had nothing to show for it. I'm pretty convinced it'll turn around, but I'll pay attention."
Walking wounded: Neither Mark Teixeira (calf) nor Brendan Ryan (upper back) seems close to coming back right now. Girardi said Ryan "may have started some light baseball activity today," but wasn't entirely sure. As for Teixeira, his activity has been limited to stretching and riding an exercise bicycle. No word on when he will be cleared to resume baseball activity yet.