Since coming up from Triple-A Sacramento last Wednesday, Moss has five hits and three home runs.
"Any time you're new to the team and it's the middle of the year, you want to come in and produce right away," said Moss, a non-roster invitee to spring training after he spent most of last season in the Philadelphia Phillies' organization.
"But a lot of times, you put too much pressure on yourself," he added. "You've just got to pull yourself back and stay within yourself and remember what it is that you do. Not everybody is Albert Pujols. You just have to do the best you can, battle, play your game and let things happen as they may."
So far, so good with the philosophical approach to the game.
"This is a great opportunity, and that's all you can ask for," said the 28-year-old Moss, who is with his fifth big league organization. "I'm very thankful for it."
For their part, the A's like what they've seen from him.
"We knew he had that kind of power," A's manager Bob Melvin said. "We saw it in spring training. We saw it in his minor league numbers. It's definitely there. It was whether he was going to do it here or not."
On Tuesday night, he wasn't the only one displaying a power swing.
Cliff Pennington and Brandon Inge also homered for Oakland. Seth Smith, a former Rockies player, doubled twice and drove in a pair of runs to help the Athletics snap a three-game losing streak and drop the Rockies to 0-7 in interleague games this season. It was Colorado's sixth loss in a row overall, matching a season high.
"We went from the position where we had to go from leading by four to playing catch up," Rockies manager Jim Tracy said. "Day after day after day, that gets to be somewhat daunting."
Colon trailed 4-0 after a tough first inning that Tyler Colvin began with a home run, his seventh of the season and fourth in three games. Michael Cuddyer, Chris Nelson and Wil Nieves added run-scoring singles.
Colon (6-6) recovered to shut down the Rockies until the fifth when Todd Helton connected on a 2-2 offering that he drove into the Rockies bullpen behind the right field wall. Colon gave up five runs and nine hits. He struck out four and walked three in winning consecutive decisions for the second time this season.
"The air is so light, he wasn't getting much movement," Melvin said. "He actually started throwing a little harder and a little straighter. As a veteran guy does, he figured out a way to give us five innings ... and we rewarded him with a win."
Jeremy Guthrie was unable to hold the Rockies' early lead, allowing the A's to bat around in a six-run third inning. He hit Jemile Weeks with a pitch to start the inning and issued a one-out walk to Josh Reddick. Smith and Inge hit successive doubles, and Moss followed with his first homer of the game, a two-run drive that smacked into a beer sign fronting the third deck.
It was the first time this season and the 32nd time in Coors Field that a homer had reached the third deck.
Pennington closed the big inning with a solo shot, driving Guthrie's first offering over the center field wall for his second homer of the season.
A frustrated Guthrie tipped his hat in a mock acknowledgment of the boos directed his way from the crowd.
"I understand where the boos come from, and like anybody else I was frustrated," Guthrie said. "It was a few unexecuted pitches. I felt really good today. Unfortunately the results weren't much different than the tougher (previous) starts."
Guthrie (3-5) allowed seven runs and eight hits in five innings. He struck out five and walked two in losing for the fourth time in five decisions.
Inge homered off Rex Brothers in the seventh to rebuild Oakland's three-run cushion.
Pennington nearly had a second homer in the eighth but Colvin made a leaping grab to snare the ball cleanly above the center field fence.
Ryan Cook walked Colvin and gave up a single to Marco Scutaro before striking out Carlos Gonzalez and Cuddyer. He then got Helton to bounce into a game-ending fielder's choice for his first career save in two chances.
All 12 of the homers allowed by Colon this season have been solo shots. ... The Rockies swept a three-game series in Oakland the last time the teams played in 2009. ... Athletics RHP Brandon McCarthy was scratched from his scheduled start Wednesday. The A's moved up LHP Tommy Milone (6-5) in the rotation to take over for McCarthy. He will face Rockies right-hander Alex White (2-4). ... The Rockies traded RHP Esmil Rogers to the Cleveland Indians for cash considerations after designating him for assignment last week following the signing of LHP Jeff Francis.