Alex Rodriguez (search) saved an 8-year-old Yankee fan from being hit by a car in Boston, the boy's grateful father told The Post yesterday.

Joe McCarthy said his son Patrick was about to cross the street in front of The Ritz-Carlton hotel Wednesday when a car came hurtling toward the boy.

"Then an arm, a very strong arm, blocked him from stepping to the street," said McCarthy, who bears the same name as legendary Yankee manager Joe McCarthy.

"He looked up and saw that it was Alex Rodriguez. My son said, 'Are you A-Rod?' and he said, 'Yeah, what's your name?' My son told him, 'I'm gonna play for the Yankees some day,' and A-Rod said, 'Is that right? Well, just be careful when you cross the street, buddy.' "

McCarthy, a born-and-bred Manhattanite who now lives on Martha's Vineyard, said that after his son told A-Rod he was a diehard Yankee fan, the superstar had another surprise for him.

"A-Rod said, 'Well, I'd like you to meet Randy Johnson, Tino Martinez and Jorge Posada.' They were standing right there with him.

"My son was blown away. He didn't even ask for an autograph. Just meeting them was enough. God bless Alex Rodriguez for making the greatest catch of his career."

McCarthy said his son, a player in the Martha's Vineyard Little League, gets a lot of grief for being a Bombers booster on the island off the coast of Massachusetts.

"Most of his friends are Red Sox fans," McCarthy said. "Even on the Vineyard, he, his 13-year-old brother and I are the sole Yankee fans out here. We feel like General Custer at the last stand.

"The Red Sox sucked for so long, now that they won, their friends think they own baseball. But we have a new cheer — '2090!'— that's the next time the Red Sox are gonna win the World Series.

"We come to Yankees Stadium as often as we can," he said. "Both my sons are killer baseball players, and their role models are Derek Jeter, Alex Rodriguez, Bernie Williams, Hideki Matsui — they genuinely look up to these guys."

Rodriguez, meanwhile, played down his heroics, telling The Post, "The child was about to enter the street. I put my arm out as the car went by."

Plucking young Patrick to safety was certainly the best play Rodriguez made that day — he was the only Yankee starter not to have at least one hit when the Bombers beat the Red Sox at Fenway Park (search) Wednesday night.