Manager Kirk Gibson brought in Thatcher, who got Ortiz to pop out to end the threat, and the D-backs wound up hanging on for the win.
"It seems like he's a lot more polished than he used to be, throws a lot more strikes," Gibson said of Thatcher. "He has a lot of deception and different angles and things that he does, and he's able to locate the ball much better than he used to be."
Thatcher had gotten Ortiz out a month earlier when he was in town with the Padres, and from that experience he put together an effective plan.
"I took things that I remembered from a month ago, so I had an idea," Thatcher said. "I had pitched here in Fenway, which is good that you have that experience under your belt, because the first time is always special. I had a plan that I wanted to execute, so it's always nice when you go into the game knowing that you're prepared."
While a left-handed specialist like Thatcher may only face one batter in a game, chances are it is going to come at a key moment and against the other team's best lefty.
"I've done this role my whole career," Thatcher said. "So I've been in big spots before, so I don't ever feel overwhelmed in any spot, which is good. I'm confident I can get out of jams. The role I'm in, I love doing it, so it's a lot of fun."
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.