Rodriguez had hoped to travel on Sunday to South Florida, where his wife is due to deliver the couple's second child by the end of this week. Instead, he will see how he feels upon waking up on Monday morning, though he refused to say whether he would accompany the Yankees to Chicago or return to New York.
Next to Rodriguez, the Yankee most interested in the delivery schedule may be Morgan Ensberg, who will fill in for A-Rod if he has to leave the team for more than one day to be with his wife or recover from the injury.
"It's something that's in the back of my mind, so it's something that doesn't ambush you because we've known it since Spring Training," said Ensberg. "It's not as though when you lose a loved one and you're thrown in there. My routine for batting [and fielding] practice pretty much remains the same."
Ensberg, signed by the Yankees as a free agent on Jan. 31 and invited to Spring Training as a non-roster player, saw action at third base for the first time this season on Saturday night. With reserve infielder Wilson Betemit on the 15-day disabled list with conjunctivitis, Ensberg becomes the primary backup plan when and if Rodriguez departs.
Oddly, Ensberg didn't have to make a defensive play on Saturday. Only one ball -- Melvin Mora's bunt single in the first inning -- came his way.
"I came up as a third baseman and that's where I feel most comfortable, so any time I get back there, it does feel like I'm riding a bike," Ensberg said. "Ironically, no plays, so it's very rare. Normally you'll get one -- a pop fly or a ground ball or something. I had a chance early with Mora, and on a 2-0 count, he bunts. ... That was my only shot."
Girardi has been impressed with how Ensberg, a full-time third baseman for most of his six seasons with the Astros and Padres, has adjusted to a fill-in role.
"Wherever we put him, he's been great," Girardi said. "Morgan, throughout his career, has played pretty much every day. He has not done that here, but he's ready to play at all times and he's ready to do for you what you ask."
Ensberg takes grounders daily at first base and three times a week at shortstop and third.
"That's just to continue to move my feet and keep that routine of moving toward first base," Ensberg said. "Never stop your feet from moving; always keep your feet moving. I like taking ground balls at shortstop because you have to move your feet more when than when you're making throws from third."
And Ensberg is warming to a role that requires him to sit for long stretches and be ready at a moment's notice.
"I've never been more prepared than I am right now," Ensberg said. "They work very hard, and that's an environment I work well in."
Pete Kerzel is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.