Chan Ho Park will never be able to shake the worry from his mind. After two hamstring injuries in two seasons, the Yankees reliever just can't help it.

"You're always worried, not just about the hamstring. You're always worried about injuries because you're old; you're not young anymore," said Park, 36, who was activated from the 15-day disabled list before last night's game against the Red Sox after missing 30 games. "So extra warm-ups, you got to do more hot tubs, whatever helps me. You're not strong like a young kid."

If he was concerned about his nagging injury Monday night, he didn't show it before the game. He entered in the seventh inning and in the eighth, he allowed a two-run homer to Kevin Youkilis and a solo shot to Victor Martinez, turning a 7-6 lead into a 9-7 deficit. He was relieved with no outs in the eighth.

Trailing by two in the ninth inning against Red Sox closer Jonathan Papelbon, Alex Rodriguez tied it at 9 with a two-run homer. Marcus Thames followed with a two-run blast as the Yankees won in dramatic fashion, 11-9. It was the first walk-off win of the season for the Yankees.

Park, who experienced discomfort while warming up during the Yankees' 6-2 victory over the Angels on April 16, had hoped to avoid the disabled list. But the team chose to be cautious with the reliever after an MRI revealed a low-level strain in his right hamstring. They placed him on the DL that day, retroactive to April 14.

Park had said the injury was in a different area and less severe than the one he endured last season as a member of the Philadelphia Phillies.

"Last year, I couldn't even almost walk," he said of the 2009 injury, which caused him to miss significant time.

The Yankees recalled Boone Logan from Triple-A Scranton/Wilkes-Barre to fill the void in the bullpen. Yesterday, they optioned 23-year-old pitcher Ivan Nova - who gave up four hits and no runs in three innings of work - to the minors to make room on the roster.

Park made two rehab starts in the past week, striking out three batters and allowing one hit in an extended spring training game in Tampa and tossing a scoreless inning for Scranton on Friday.

"I feel good about running, stretching and exercise is pretty good," said Park, who last appeared for the Yankees on April 7 in Boston. When asked about his expected pitch count limit, he said: "Two innings is usually what I do."

Park, who was signed to a one-year deal in February, was 1-1 with a 4.76 ERA in three outings this season.

SUBSCRIBE

Unlimited Digital AccessOnly 25¢for 6 months

ACT NOWSALE ENDS SOON | CANCEL ANYTIME