Alex Rodriguez will arrive at spring training intent on being the Yankees' regular third baseman this season, a person familiar with his thinking said Thursday.

Rodriguez was undeterred, the source said, by the signing of Chase Headley to a four-year, $52-million contract to play the position Rodriguez occupied before his year-long suspension resulting from Major League Baseball's Biogenesis investigation.

"Alex's mind is that job's not Headley's, it's Alex's to lose," the source said. "That's what he thinks. Alex is going into training camp thinking that he is the starting third baseman, that if there's a competition, Headley's got to win it from him. It doesn't matter about the money, what they signed Headley for. This guy [Rodriguez] can play."

DataA-Rod's career home runsInteractiveAlex Rodriguez's injury historyDataMLB drug suspensions database

Rodriguez, who will turn 40 in July, has three years and $61 million left on his contract.

Told of Rodriguez's thinking, general manager Brian Cashman said, "We signed our third baseman, but Alex has to come in to compete for as much playing time as he can possibly get, so I would expect him to come in to be a two-way player, which is offense and defense."

The source said Rodriguez has been working out seven days a week in Florida. "He's hitting every day, running every day, training really hard," he said. "He's been training hard for months. The guy's cut, ripped. The fact that people think he's overweight -- we all wish we could be that overweight."

advertisement | advertise on newsday

Even though position players are not required to report to the Yankees' spring training camp before Feb. 25, Rodriguez could opt to attend sooner.

"A lot of guys go into Tampa early on their own. It's a voluntary thing," Cashman said. "If people want to come in, our offices on the minor-league side are open. He's a member of our team. He's got full access like anybody else."

Rodriguez is expected to eventually address the issues that led to his suspension.

Yankees videos

"Alex learned a lot in the last year," the source said, "and by the time he gets back on the field, it will almost be a year and a half. He's changed as a person. He's put his head down and he's working hard because he wants to play the game and respects the game, and he knows that he made some mistakes and the best way to atone for that is to just put your head down and go."