The team announced the move before Tuesday night's game against the Chicago White Sox. Matsui was immediately inserted into manager Joe Maddon's lineup, batting sixth and starting in left field.
After hitting a fly to left in the second, Matsui connected for a long two-run homer to right during the fourth. It was his first home run since Sept. 19 against Texas while with Oakland. He finished the night 1-for-4 as the Rays lost 7-2.
"You'll see him in left field, you'll see him as a DH and you'll see him pinch hit," Maddon said before the game. "I'm just really eager to have him here. A very classy kind of a guy."
Matsui, who turns 38 on June 12, played 13 games with Durham after signing a minor league contract with Tampa Bay on April 30. He hit .170 with four RBIs for Durham, where he played in left field four times.
"Defensively, I didn't have any issues at all," Matsui said through a translator. "So, I think I was able to get some games in and get ready for this."
Matsui has played nine seasons in the major leagues with the New York Yankees (2003-09), Los Angeles Angels (2010) and the Athletics (2011) following a 10-year career with the Yomiuri Giants of Japan's Central League.
"It's just like with any veteran player," Rays executive vice president of baseball operations Andrew Friedman said. "We're not necessarily looking at stats, how they do. It's just like it's spring training. The most important part is that they feel good and they've got their timing down. He felt like he was now at that point."
Information from The Associated Press was used in this report.