Sweeney winced and grabbed his arm. Both said they thought initially that Sweeney's career might be in jeopardy.
"It was almost career-ending, but fortunately, the arm held up," Sweeney said.
The 37-year-old Sweeney felt like the proverbial kid in a candy store on Thursday as he basked in his new surroundings. He's been an All-Star five times, but in 16 years in the Majors, he has never been on a playoff team.
"This is a dream come true," Sweeney said. "It's a chance to go to the playoffs for the first time in my career, and that's a great joy, to say the least. It's great to share a locker room with these guys, and I don't take that for granted for one second."
To make room for Sweeney, the Phillies designated for assignment Cody Ransom, who was hitting .190 in 42 at-bats.
Manager Charlie Manuel is giving Sweeney at least a day to adjust. Ross Gload started at first base in Thursday night's series finale against the Marlins.
"I'll turn him loose at Citizens Bank Park," Manuel said on Thursday, a night before the Phillies open a six-game homestand with a matchup against the Mets.
The manager added: "He's a good hitter. He's a line-drive hitter who puts the ball in play and takes a lot of pride in his hitting. He should like our [hitter-friendly] ballpark."
Concern about Sweeney's health appears to be exaggerated. He's been on the disabled list twice this season with back woes, but both moves were likely more tactical than health-related.
Sweeney said that the first problem, a back spasm, had subsided within a day, and on the second day, "I was taking batting practice when they put me on the DL."
Sweeney recalled talking during Spring Training to Cliff Lee, who pitched for the Phillies last season. Sweeney said that Lee told him, "That's the most fun I've ever had in baseball. Great team, great clubhouse."
"To join a team that is already primed and ready to go is very attractive," Sweeney said. "Whatever Charlie wants me to do, I'll do it. If he wants me to bunt, pinch-run, play first base, I will do everything in my power to do it. I'm just trying to be a small piece of an already great puzzle."
Sweeney paused a moment then added, "And hold the fort down while Ryan [Howard] is out."