The Yankees have lost their third baseman for at least 10-12 weeks and their first baseman for at least two.

Kevin Youkilis has a herniated disc in his back and will undergo surgery on Thursday, sidelining him for 10-12 weeks at the minimum, Yankees GM Brian Cashman announced Tuesday afternoon. Meanwhile, Mark Teixeira was placed on the 15-day DL with inflammation in his right wrist.

With Alex Rodriguez still rehabbing in Tampa, the Yankees will use David Adams at third base. Rodriguez is not expected back until after the All-Star break and is also facing the possibility of an MLB suspension due to his alleged Biogenesis ties.

At first base, the Yankees will use Lyle Overbay for Teixeira, who hopes he’ll return after the 15-day DL stint, saying, “It’s just inflammation.” Still, Teixeira essentially admitted there’s no objective reason to believe that even when he does come back that his wrist won’t force him to miss time again.

“’Cause I’m a positive thinker,” he said. “I’m gonna hope for the best.”

Teixeira also said that since he played 19 of 20 days before leaving Saturday’s game, he might have to sit for a day per week once he returns.