"We're going to play it safe," manager Joe Girardi said. "We don't feel he's any worse than he was before, but we're just going to play it extremely safe here and know that we'll have a player in 15 days."
Rodriguez initially injured his calf on Monday, leaving a game against the Tigers after four innings. His return to the lineup on Friday night as the designated hitter lasted all of one at-bat. With his only swing of the night, Rodriguez grounded out to third and jogged very gingerly out of the box. He was lifted for a pinch-hitter two innings later.
Girardi had said before the game that although he didn't expect Rodriguez to play this weekend or even in the following series in Toronto, he did not think the disabled list was likely. That thought changed sometime after Rodriguez arrived at the ballpark.
"[General manager Brian Cashman] talked to the doctors and the trainers, and we just felt it was probably in the best interest to put him on the DL," Girardi said.
Rodriguez and the Yankees maintain that the most recent instance of his injury is no worse than the first one earlier in the week. The third baseman said on Friday that, since he's never had a calf injury before, he's had trouble determining what exactly he can play through.
With Rodriguez out, the Yankees will turn to youngsters Ramiro Pena and Eduardo Nunez to fill his considerable shoes. Pena is batting .197 on the season, but he does have 16 RBIs on just 23 hits. The Yankees are 22-8 in games he starts.
Nunez, meanwhile, made his first Major League start on Saturday, driving in the go-ahead run in the seventh with his first career hit.
"Those guys are what we have right now, and we'll continue to evaluate on an everyday basis," Girardi said. "These guys have done a pretty good job filling in."
Indeed, Saturday's win improved the Yankees' record to a remarkable 11-0 in games in which Rodriguez does not appear. New York was just 21-17 in such games a season ago.
"You can't help but miss a guy like Alex, but we're going to do our best," Mark Teixeira said. "We all have to continue to play well and pick each other up."
Right-handed pitcher Ivan Nova will be called up to replace Rodriguez on the roster. Nova will make his first career start on Monday in Toronto.