The decision, which was announced just minutes before game time, came on the same day that Longoria felt "very minimal" pain in his recovering right wrist after taking swings with a fungo bat, followed by a regular baseball bat.
"It went really good," said Longoria, who has been sidelined since Aug. 8 with a fractured wrist. "I took about 15 swings with the fungo and it felt fine. Then, I got about 30 swings with a regular bat and it felt pretty much the same as swinging the fungo, which is obviously a good sign.
"[It's as] good as it's ever felt," Longoria added. "It's almost 100 percent."
Longoria was not in the lineup for Saturday's game at Rogers Centre, and his contribution to the Rays will be, at least for the time being, minimal. It's not likely that he will see any action as a hitter until he is fully healthy and has participated in a few batting practice sessions.
Instead, Tampa Bay could likely use him as a pinch-runner or a defensive replacement late in games. His injury has not stopped him from staying in game shape, as he has been running, playing catch and taking ground balls on a regular basis.
"I've been wanting to be activated for the last five days," Longoria said. "Just to be in there and kind of prepare myself mentally."
For now, Longoria, who did not hit any baseballs on Saturday, hopes to hit balls off a tee on Sunday. Then, if all goes well, he would like to participate in a live batting practice on Monday in Boston. The third baseman also indicated that he is aiming to return to the starting lineup for Tampa Bay's game at Yankee Stadium next Friday.
Longoria was placed on the DL after being hit by a pitch from Seattle right-hander J.J. Putz.
The 22-year-old third baseman, who is one of the front-runners for the American League Rookie of the Year Award, has been one of the Rays' best hitters this year. In 104 games, he is batting .278 with 22 home runs, 27 doubles and 71 RBIs.
With Longoria activated from the disabled list, there was no need for the Rays to make a corresponding roster move because of the expansion of Major League rosters on Sept. 1.
David Singh is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.