OAKLAND -- Derek Norris thought it was a large rat. So did manager Bob Melvin. Turns out it was a possum -- a rally possum.
The creature lurked near the left-field warning track at the Coliseum late Monday night as the A's staged a 10th-inning rally against the Rays, capped by Norris' game-winning RBI single that sealed a 3-2 victory, their eighth walk-off win of the season.
"He's been out here before when we're warming up," said starter Jeff Samardzija. "We're going to have to give him a name or a jersey.
"We'll keep feeding him, and as long as he keeps giving us enough wins, we'll be all right."
Monday's win afforded the A's another day as baseball's best team, as they held a one-game lead in the American League West over the Angels, who won at Dodger Stadium.
Sam Fuld got things going in the 10th with a one-out base hit, leading to back-to-back walks to John Jaso and Josh Donaldson, whose near-check swing on what would've been a third strike got Rays manager Joe Maddon ejected. Brandon Moss struck out for the second out, and Norris went down, 0-2, in the count, before poking one into left field for the game-winning hit.
"Sometimes [former A's closer Grant Balfour] falls into patterns, but tonight he was mixing really well," said Norris. "Once he gets runners in scoring position, he turns on another switch. I saw it time in and time out here. So I was just looking for something out over the plate. I thought anything back up the middle didn't have to be too hard to get through, and fortunately it got enough to get through."
"Just got beat tonight by a good team," said Balfour, who spent the previous three seasons in Oakland. "That was it, plain and simple."
The A's left the bases loaded in each of the first two innings vs. Alex Cobb before capitalizing on another opportunity in the third, with the streaking Josh Reddick boarding on a base hit and coming around to score on a double from Jed Lowrie, who enjoyed a three-hit night.
Donaldson's RBI single in the sixth tied the game, and the A's would go on to strand the bases loaded again in the seventh. By the time they got to the fateful 10th, they had left 15 on base.
Samardzija kept his club in the game with a seven-inning, two-run outing. He gave up a solo homer to Evan Longoria to lead off the second and kept the Rays off the board again until the fifth. It was at the end of the sixth when he tallied his 100th pitch of the night, and Melvin stuck him back on the mound for the seventh, which the righty handled with ease.
Samardzija induced 13 ground-ball outs on the night, walking just one and fanning three in the no-decision.
"Seems to be my M.O. since I've been here," he said. "Go out and throw some innings and then watch these guys put on a show at the end of the game. I love this team, man. I love how they play, they don't quit. Every at-bat means the world to each guy, and you see that in their emotions, how they react to each at-bat.
"It's fun to watch, and as a pitcher, it makes you go out and battle every inning, because you understand that every run counts."
Luke Gregerson pitched a scoreless eighth, and lefty Sean Doolittle wiggled his way out of a wild ninth.
James Loney left off the frame with a base hit, and pinch-runner Sean Rodriguez advanced to second on a sacrifice bunt in advance of Lowrie's fielding error that put runners at the corners with just one out for pinch-hitter Brandon Guyer. Guyer got a bunt down but right in front of Doolittle, who flicked it to catcher Norris for the second out before fanning Kiermaier to close out the inning.
Ryan Cook pitched the 10th unscathed. That's when the possum came out for a peek.
"Never know what you're going to see here," said Melvin, smiling.
Jane Lee is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.