The retiring hurler surprised long-time Athletics employee Julie Vasconcellos before Wednesday's game at the O.co Coliseum, delivering an early dinner to her mail-room office. They spent about 30 minutes together before Rivera took the field for batting practice with his teammates.
"This is my way to say thank you, thank you for what you do," Rivera told Vasconcellos, according to The Associated Press. "Twenty-five years, Julie, that's great! You're special, Julie, that's what it is. People here love you."
Rivera has said that he wants to take the opportunity to thank diehard fans and long-time club employees at each of the Yankees' road stops this season.
Vasconcellos, the A's office services coordinator, has worked for the club since 1989 and is involved in aspects of the organization ranging from the front office to the mail needs of the home and visiting clubhouses.
"Oh, my heart's going to town, oh my God," Vasconcellos told the AP. "I'm shaking. ... Oh, this is too funny, thank you."
Bryan Hoch is a reporter for MLB.com. Follow him on Twitter @bryanhoch and read his MLBlog, Bombers Beat. This story was not subject to the approval of Major League Baseball or its clubs.