"With everything that has happened, it seems like the starters are expecting something bad is going to happen that's going to lose us the game," Nieves said. "We have to change that mentality and stay positive."
Murphy's Law was in full effect at Coors Field. Guthrie (3-5) was handed a 4-0 lead after the first inning, but unraveled in the third. On an 0-2 count, Guthrie hit Jemile Weeks, who later advanced to third base on a wild pitch, then walked Josh Reddick. Seth Smith and Brandon Inge followed with back-to-back doubles before Brandon Moss crushed a hanging curveball that ended up in the third deck and gave the A's a 5-4 lead.
A solo shot off the bat of Cliff Pennington one out later made it 6-4 and invited a chorus of boos from the 33,635 in attendance.
"It was a bad inning, but it was six runs," Nieves said. "Everybody has bad innings, but you hope it's only two, three runs. Jeremy will be fine. He's just frustrated."
Guthrie struck out Bartolo Colon and, on his walk back to the dugout, grabbed the bill of his hat and extended it to the crowd -- a gesture he chalked up to frustration.
"I understand where the boos come from," Guthrie said. "I was frustrated with myself. The fans didn't give up two home runs or six runs."
Guthrie had tipped his cap earlier in the game, too, after escaping a bases-loaded jam in an ugly first inning. Guthrie said that was to nobody in particular.
"He seemed to be discouraged, absolutely," said Rockies manager Jim Tracy.
Moss became the first player this season to hit a ball into the third deck at Coors Field and the 32nd in stadium history. He took Guthrie for a ride again in the fifth inning, with a shot to the second deck in right field, his third of the year.
"It was good to get the big inning and then add on a little more," Oakland manager Bob Melvin said.
It was Guthrie's fifth straight start in which he allowed at least five runs, made more frustrating considering Oakland ranks last in the Majors in batting average and slugging, second-to-last in on-base percentage and third-worst in runs scored.
"When I struggled in the past, I lost a lot of confidence," Guthrie said. "Right now, I believe I can get people out. It just hasn't happened."
A bright spot in the midst of Colorado's slide has been the play of Colvin. In the last three games, Colvin is hitting .700 with a double, four homers -- including a leadoff blast Tuesday -- six RBIs and five runs scored. Colvin also received a standing ovation when he robbed Pennington of a home run in the eighth inning.
"Got under it enough with time to get to it, I was lucky enough to catch it," Colvin said. "I saw where the ball was and once you feel where the track is, you guesstimate where to jump."
Todd Helton knocked his sixth home run, a solo shot off Colon in the bottom of the fifth.
The Rockies have played well defensively and are still putting up substantial numbers, scoring at least five runs in each of their last three losses. But those losses are starting to take their toll.
"It's a script we've been following quite a bit," Tracy said. "We were in a position from the third inning on where we had to play catch-up. Day after day after day, that gets somewhat daunting."