"He's just a great guy to have around. The fact now that he's active will only enhance that."
Giambi's activation was part of a handful of roster moves that altered the makeup of the bench and bullpen.
Cleveland also promoted left-handed reliever Nick Hagadone from Triple-A Columbus. To clear room on the active roster for Giambi and Hagadone, the Indians optioned starter Corey Kluber to Triple-A and placed reliever Matt Albers on baseball's Paternity List.
The 42-year-old Giambi -- signed to a Minor League contract over the winter -- was originally in the plans for the Opening Day roster, but he was placed on the DL at the end of Spring Training. Now on Cleveland's bench, the veteran left-handed slugger will serve as a part-time designated hitter and pinch-hitter, garnering most of his at-bats against right-handed pitchers.
"I'm no longer a house guest. I'm part of the ballclub," said Giambi, who might be in the starting lineup Sunday. "It's fun. I'm excited about it and ready to get going."
Giambi served a similar role over the past few seasons for the Rockies, hitting .245 with a .370 on-base percentage over 211 games from 2010-12. In that span, Giambi hit 20 homers, drew 72 walks and knocked in 75 RBIs.
"It's great to have Jason active," Indians general manager Chris Antonetti said. "He made a huge impact on our team in the time he wasn't even on the field. We're excited to actually now have him on the active roster so he can make an impact on the field, in addition to off the field."
Hagadone was originally included on Cleveland's Opening Day roster, but he was optioned April 2 in order to place lefty starter Scott Kazmir on the roster. Kazmir was subsequently moved to the 15-day DL with a right ribcage strain, but by adding Kazmir to the 25-man roster, Cleveland was able to backdate his DL stint to the first game of the season.
"He made the Opening Day roster," Francona said of Hagadone. "We had the Kazmir thing happen, so we had to do the move. We explained it to Nick. To his credit, he didn't pout. He did it understanding that we wanted him here. We told him we'd try to get him here, and we did."
Kluber was promoted from Triple-A Columbus on Wednesday for a start against the Yankees, but that game and Thursday's contest were postponed because of rain. As a result of the pair of rainouts, and a scheduled team off-day coming Monday, Cleveland no longer needed to carry Kluber on the pitching staff.
Albers can remain on Major League Baseball's Paternity List for up to three games.