Can you name the athletes by the picture?

The doctor answered the phone and heard the familiar voice of a colleague on the other end of the line. "We need a fourth for poker," said the friend.
"I'll be right over," whispered the doctor.
As he was putting on his coat, his wife asked, "Is it serious?"
"Oh yes, quite serious," said the doctor gravely. "In fact, there are three doctors there already!"