Mark Teixeira feels he still has not reached his full potential. The New York Yankees have US$180 million riding on it.

The Yankees officially signed Teixeira to an eight-year, $180 million deal - the fourth-richest contract in baseball history - before introducing the first baseman during a news conference Tuesday afternoon.

A two-time Gold Glove winner and career .290 hitter, Teixeira already has established himself as one of baseball's top young stars.

But the slugger knows he will be expected to help lift the Yankees to their first World Series title since 2000.

"No one expects more from me than I already expect from myself," Teixeira said. "I've been given a great gift, but I've yet to tap my full potential."

Teixeira, 28, initially agreed to the lucrative contract on December 23, less than a week after the Yankees spent a combined $243.5 million on free agent pitchers CC Sabathia and A.J. Burnett.

But the completion of the deal was pending paperwork and Teixeira passing a physical, meaning the Yankees had to wait two weeks to unveil their latest high-priced acquisition.

The wait evidently was well worth it for Teixeira, who was all smiles Tuesday afternoon while accompanied by his wife, numerous Yankees officials and his agent, Scott Boras, during what was perhaps the final event at the old Yankee Stadium.

"My goals are the same goals as the Yankees - that's to win a World Series," the former All-Star said. "I've been blessed throughout my career, and now I'm even more blessed to be joining the (Yankees)."

New York, reeling from missing the playoffs for the first time since 1993, have spent a whopping $423 million this winter on Teixeira, Sabathia (seven years, $161 million) and Burnett (five years, $82.5 million).