|Appearances||Jack O'Malley - List of Appearances|
|Portrayed By||Tom Cavanagh|
Jack is a former professional golfer. Throughout Season 3 he participates in a medical trial in an attempt to cure his lupus disease.
Jack O'Malley is a carefree and laid back man who jokes around with everyone, especially Jill, though doesn't seem to actively want to pursue a relationship after seeing how in love Jill and Hank are. When faced with his diagnosis of lupus he brushes it off and opts to question his doctor about her potential role in a cheesy old sitcom he used to watch.
Season 2 Edit
Jack is first introduced in the episode "Mulligan", where HankMed is working for three days at a charity golf tournament. As a golf pro, he is paired up with Jill Casey and together they play against an old, severely drunk couple who freak out when they are told they will be playing with Jack O'Malley. Jack and Jill hit it off, Jack even going as far as pointing out that together they are "Jack and Jill". While driving to another hole, the drunk couple almost hits them with their golf cart causing Jack to have to swerve off the path and thus throwing Jill out of the cart. Despite Jill only receiving minor injuries, Hank shows up and remembers that Jack may have something wrong with his fingers and Jack explains he had trouble grasping the steering wheel. Hank diagnosis that Jack may have a condition that causes progressive hardening of the tissue of his hand. Jack admits that he has know for around 18 months, but doesn't want surgery because he thinks it will keep him off tour too long. Divya, while in England, finds a possible treatment for Jack. Hank injects Jack's hands with a new drug but he doesn't feel any different. So, Hank bends his fingers backwards and miraculously his fingers are all better. Jack goes off and does extremely well in his next tournament.