Richardson suffered a compound fracture of the ring finger on his right hand earlier in the game.
"I don't know if I'm allowed to tell you guys this but he dislocated his finger," Baldwin said. "It came out of his skin and he's sitting there bleeding, his bone is out of the skin. He goes into the locker room, sews it up and tapes it up, comes back out and scores the game-winning touchdown. That's the mentality that we have here and I couldn't be more proud of these guys."
The injury occurred on Seattle's opening drive, when Richardson reached down for a low pass from Russell Wilson that skipped off the turf. He immediately signaled toward the sideline while running off the field then went into the locker room, where trainers applied stitches.
"It hurt a lot," Richardson said, adding that it was "nasty."
Richardson returned to catch two passes, including the go-ahead, 9-yard touchdown with 7 minutes, 6 seconds remaining in the fourth quarter.
"He went back in and caught the game-winning touchdown pass with it," coach Pete Carroll said. "Good stuff."
Richardson is in his fourth season out of Colorado and is one of Seattle's top three receivers along with Baldwin and Tyler Lockett. Carroll didn't seem concerned that his finger will be an issue going forward, noting how he was able to return to the game.
"That shows his toughness," Wilson said. "To be a receiver and have your fingers sewed up and to battle and to come back in, that shows his courage. There are so many guys like that, constantly, consistently, on our football team, but that was a great example of that tonight."