Matt Holliday hit a three-run homer during a four-run 11th inning to help the Athletics beat the Tampa Bay Rays 4-1 on Tuesday night.
"We need to start winning games because it's been frustrating," Holliday said after Oakland won for just fifth time in 15 games.
"That was something," Athletics manager Bob Geren said. "Holliday, with two strikes, hit one of the longest balls I've seen all year."
"It's definitely not on J.B.," Nelson said. "That's where I need to step up."
Santiago Casilla (1-1) pitched a scoreless 10th inning for the win, which stopped Oakland's four-game losing streak.
Willy Aybar hit a solo homer for Tampa Bay in the bottom of the 11th.
The defending AL champion Rays (20-21), who had won four straight, failed in the attempt to move above the .500 mark for the first since they were 4-3.
"That's the kind of game that we've permitted to get away from us this year way too often," Tampa Bay manager Joe Maddon said. "We've got to starting winning those kind of games on a consistent basis."
"I've always said it's not how you pitch, it's when you pitch," Shields said. "Our team is a good team, and we're going to come back from this. Their pitcher did a great job of counteracting what I was doing out there."
Shields is 1-3 in his last six starts despite allowing 16 runs -- 13 earned -- in 40 2/3 innings.
Athletics left-hander Josh Outman gave up three hits, one walk and struck out six over six scoreless innings.
"Obviously I'd like a win, but the team getting the win at this point is more important," Outman said. "I think this could right the the ship for us and we can stop giving up big numbers and let the offense work."
Oakland starting pitchers had given up 31 runs -- 23 earned -- over 13 innings in the previous four games. In losing all four of those games, the Athletics allowed 47 runs overall.
Orlando Cabrera started the first with a single and went to second when Holliday drew a two-out walk. Shields then started a stretch of retiring 17 in a row by inducing an inning-ending grounder from Jason Giambi. The run ended when Holliday hit a one-out single in the seventh.
Holliday had two hits in four at-bats. He entered 1-for-14 against the Rays this season.
Upton had a one-out single in the bottom of the eighth against Andrew Bailey and went to third on a single by Crawford. After Evan Longoria struck out and Carlos Pena walked on a 3-2 pitch to load the bases, Bartlett struck out swinging.
Bartlett went 1-for-4 with a walk, and is hitting .380 this season.
Rays C Dioner Navarro (pinkeye) was out of the lineup for the second straight game, but entered as a defensive replacement in the ninth. Maddon said with a smile that Navarro's eye looks like a "scene from a horror film." ... Giambi went 0-for-3, and is hitless in 13 at-bats overall, against Shields. ... Crawford stole his 25th base of the season in the 10th. ... Tampa Bay's streak of scoring three or more runs in 21 straight games -- which was the longest active stretch in the majors -- ended.