There may not have been any excuses, but there were clues as to where the 2015 National League Cy Young Award winner was off his game.
"Just too many hittable pitches in the middle of the plate," Arrieta said. "When you pitch [at Coors Field], there's a lot of room. The balls found some space."
Arietta is now 0-2 at Coors Field with a 14.54 ERA in 8 2/3 innings over two starts. He's given up a combined 22 hits and 18 runs (14 earned) there.
"They've got one of the better offenses in all of baseball, especially at Coors Field," Arrieta said. "I wanted to come into this game and establish strikes with all my pitches. I did it pretty well, almost too well with too many hittable pitches, really. Not necessarily ones they hit for a lot of power, they just were able to find some holes in the outfield grass. It's a big yard. Unless it's hit at somebody, it's going to pose a threat."
Finding too much of the plate can be an issue, especially for a pitcher who has deviated from his habit of lighting up radar guns as a way of avoiding barrels.
"There's something different," manager Joe Maddon said of Arrieta's struggles Tuesday. "They're not missing it as often. Velocity obviously is not the same, just looking at a [radar] gun. The last couple of games, he was a little bit higher velocity than I saw today."
Arrieta's two-seamer has dipped from an average velocity of 95.3 mph in 2015 to 92.1 in '17, according to Statcast™, and he was in the low 90s Tuesday, topping out at 93.6.
His vertical movement is also down more than a full inch this year, averaging 6.73 inches of movement on his two-seamer heading into Thursday, and Statcast™ reports the spin on his curveball was 2,702 rpm for the season, but just 2,596 for the 12 curves he threw Tuesday.
"He sinks the ball, he's got the four-seamer, the cutter, the slider, curveball -- so he's going to throw you everything," Carlos Gonzalez said after walking and singling against Arrieta. "You've just got to stay in the zone, because he's having some issues with throwing strikes."
Arrieta, who entered the day with a 10.5 K/9 mark, notched only three strikeouts in his short outing.
"He just left some pitches up that he's not used to leaving up, and we took advantage," Rockies third baseman Nolan Arenado said. "We got a couple bloopers and a couple lucky hits."
Arrieta admitted he relied too much on his fastball and slider and didn't use his change and curve enough.
"I didn't mix well enough," Arrieta said. "I need to just continue to prepare and refine my pitches and throw them all for strikes, because if I'm doing that, it's going to be tough for teams to score a lot of runs."