"It just kind of grabbed my lower back and I was able to walk it off. [It was] just a temporary pain and I should be fine [Friday]."
The first person other than Papelbon to notice was Sox third baseman Mike Lowell.
"You don't usually see a pitcher picking up his leg and stretching, so I just wanted to ask for time to see if he was all right," said Lowell. "He looked good enough, so you keep your fingers crossed that he's OK."
"I just starting walking it off and making sure the pain wasn't coming back and back and back again," Papelbon said. "Once I told him that the pain was starting to dissipate in my lower back, I said I was going to be able to go."
After Lowell asked for time, Red Sox manager Terry Francona came out with trainer Jim Rowe to assess the situation.
Papelbon was successful in convincing his skipper that he was fit to face a batter who, with one mistake, could tie the game with one swing.
"He got his spike stuck or lodged in the rubber on one pitch," Francona said. "He felt it in his back. I think the biggest thing was he wanted to make sure he was OK. That time of the game, you don't want to leave a pitch out over the plate because you're feeling something, a part of your body.
"I wanted him to reassure me that he was OK -- not only OK physically, but able to execute a pitch and not be thinking about his back. He said it was no problem."
One batter earlier, Papelbon, during a long at-bat to Frank Catalanotto, stretched his arms to his feet after delivering a pitch that was fouled off.
Papelbon's next pitch was fouled off before Wells grounded back to the Boston closer, who jumped off to the first-base side of the mound without a problem and threw to first for his 11th save in as many chances, sealing Boston's 7-4 win.
"Anytime you feel anything [is a little scary, because] no one wants to go on the DL," added Papelbon. "You want to be able to go out there and help your team day in and day out."