Somehow, though Donnie Walsh still isn’t exactly sure how, he’s been plopped in the middle of America’s most famous infectious disease doctor’s basketball claim to fame. “I said, ‘How did that happen?’” Walsh said in a phone interview Wednesday. “This has been one of the most out-of-the-blue things I’ve ever been involved in.” Sixty-two years ago, Anthony Fauci took his high school’s 1-16 team onto Walsh’s court — and won.