Following Friday night's 5-0 loss to the Royals, Twins manager Ron Gardenhire said he had received a text message from Bartlett.
"He appreciated the chance here," Gardenhire said. "He was good for us in Spring Training. We're going to miss him. One of the greatest kids you'll ever meet. He's making a decision for him and his family."
Antony said the Twins didn't have a hint that Bartlett might be thinking about retirement when he recently reported to Class A Advanced Fort Myers for a rehab assignment after sustaining an ankle injury.
"He went out as scheduled," Antony said. "It caught me off-guard, caught me by surprise."
Bartlett didn't sound dejected on the phone, according to Antony.
"Not at all," Antony said. "He sounded like a guy who had been thinking about this and was comfortable that this is what he wants to do."
The Twins had planned for Bartlett to play about a week for Fort Myers before moving up to Triple-A Rochester to continue the rehab assignment.
After making the Opening Day roster, Bartlett was working on a split contract -- meaning compensation is based on whether the player is in the Minors or Majors.
"I don't think any of that is going to come into play," Antony said. "He wants to just retire, similar to the [former Royals starting pitcher] Gil Meche thing. He told me, 'You guys treated me great. You gave me a chance to come back and do this.'"
Bartlett, 34, was 0-for-3 in three games this season. He sat out the 2013 season before coming back this year. Bartlett entered 2014 with a .271 batting average in 889 Major League games.
"I think he could definitely contribute to the team," Antony said. "What he was going to do production-wise on the field was still up in the air. But I know Gardy [manager Ron Gardenhire] was very excited about what he could bring to the team. The way he went about things, the example he set, the leadership role he was playing. There were a lot of intangibles in how he fit on this team."
Robert Falkoff is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.