However, Latos tossed four solid innings against the Rockies. The 6-foot-6, 225-pound 21-year-old allowed two runs on three hits, and walked one. He threw 75 pitches, 51 for strikes.
While he was outdueled by Rockies ace Jason Marquis (12-6), who beat the Padres, 6-1, Latos earned praise from his teammates and manager Bud Black.
"I thought he came out of the chute extremely well," said Black. "You guys saw life on the fastball early. I think you saw a good sharp breaking ball as the game progressed, a couple good changeups. I thought he showed some poise in his first Major League start. I think we saw a lot of positive signs and he will pitch Friday in Washington against the Nationals."
"He certainly showed that he belonged," said Chris Young, his next door lockermate. "He exhibitied a lot of poise and had a lot of pop on his fastball."
Latos was touched up for a home run in the fourth inning by Ian Stewart, who hit a 3-2 pitch into the right-field bleachers. It was Stewart's 17th home run of the season.
The other run Latos yielded came in the third when Carlos Gonzalez singled, was sacrificed to second by Marquis and came around to score on a throwing error by Padres catcher Jose Lobaton, who tried to throw out Gonzalez stealing third.
"I was nervous, but it was great," said Latos. "Being out there on a pro field was a great experience. I was down in the zone for the most part. I just made one mistake and that was the home run. Otherwise everything else was fine.
"I really didn't pay much attention to the crowd," Latos said. "[Heath] Bell told me, 'When you're on the mound look just ahead of you and focus on the batters.'"
Asked what he wanted to work on in his next start, Latos said, "I want to try to keep calm and keep my nerves in check and do my own thing.
"The first inning I felt I was going to get sick on the mound. The second inning I felt I was going to get sick on the mound. The third and fourth innings the same thing. I walked into the clubhouse and took a deep breath after I was done. And I'm good now."
Latos said he hopes that feeling goes away when he takes the mound Friday in Washington.
"The whole experience was more than I expected," said Latos. "It was incredible. I wouldn't change it. You only have one debut so I wouldn't change it."
Latos's biggest battle was a 12-pitch confrontation with Todd Helton in the first inining. Latos wound up walking Helton, but had him on the ropes a couple of times. He followed that up by striking out Brad Hawpe to end the inning.
"That's why he's a sure Hall of Famer," said Latos. "He slaps away all the pitches that he doesn't like and looks for the pitch he can drive. I thought I had him when he fouled tipped a ball, but he wound up getting a walk."
Latos did retire Helton on a line drive to right in the third inning.
As for Hawpe, he hit his 15th home run off Padres reliever Mike Ekstrom in the sixth inning.
Ekstrom and Luis Perdomo combined to give up four runs in the sixth, including a two-run double by Marquis, who had a great all-around game on Sunday.
The Major Leagues' win leader lost his shutout bid in the seventh inning when Adrian Gonzalez doubled leading off.
Will Venable singled and pinch-hitter Kevin Kouzmanoff got a sacrifice fly with a deep drive to center field. Labaton, who was catching Latos, got his first Major League hit when he singled leading off the eighth inning against Marquis, who gave up just five hits.
"You look at Marquis and what he's accomplished," said Black. "You have a guy who was on the corners and changing speeds. He knew that going in he would throw sinkers and changeups and cut fast balls around the plate, and that produced a lot of ground balls."
The Padres hit into 17 ground-ball outs against Marquis.
Of course beating rookie pitchers is nothing new to the Rockies, who have won each of their past nine games against rookie starters, including the Padres' Josh Geer. They are 10-3 this season against rookie starters.
Sandy Burgin is a contributor for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.