"You see it but I can't say I thought about it a whole lot," Luebke said. "It's the sixth inning. There's still a lot of game to go yet. It's not something you think about until the last inning."
The Padres have never thrown a no-hitter in their 43-year history, though 19 times they've held an opponent hitless into the eighth. The last time was July 9 when five pitchers kept the Los Angeles Dodgers hitless through 8 2/3 innings before Juan Uribe broke it up with a double.
"I think you always (think about it) because you want it to happen for your guys," San Diego manager Bud Black said. "You're always aware of it as you move deeper into the game. We've seen it a number of times in the past."
Luebke (6-9) tried to become the first pitcher in franchise history to accomplish the feat. He walked three and retired 12 straight at one point through five innings. He got Chris Nelson to line out to open the sixth before walking Eric Young Jr.
Luebke momentarily preserved the no-hitter in the sixth when he slid to grab Dexter Fowler's slow roller near the mound and threw out the speedy outfielder at first for the second out of the inning.
"I was definitely thinking this was his night," outfielder Cameron Maybin said.
One batter later, Ellis ended the no-hit bid with his seventh homer to make it 8-2. It was Colorado's only hit of the game.
"A game like that, the only way you let a team back in is by putting guys on base yourself," Luebke said. "I just wanted to pound the zone."
It wasn't a guarantee Luebke would finish the game had he kept the no-hitter going. Entering the sixth his pitch count was 86 and he finished the game with 119 pitches, a total due in large part to nine three-ball counts.
"That would have been a tough decision," Black said. "There probably would have been a limit at some point."
Luebke was lifted for a pinch-hitter in the eighth. He struck out a career-high nine.
"You don't like to give credit to pitchers," Ellis said. "You might have to do it tonight."
Ernesto Frieri pitched two hitless innings to finish the game. The Rockies have lost five straight and six of seven.
"We obviously don't have some of the best players out there," Ellis said. "But the guys that are out there are playing hard. We're just not winning a lot of games."
San Diego broke it open in the fourth and chased Millwood. Jeremy Hermida led off with a walk and scored on Cunningham's homer to left-center, his second.
One out later, Luebke singled to right and Maybin hit the first pitch he saw into the right-field bleachers for his ninth homer to make it 7-0.
"I made a lot of hard outs the past week and a half, and it was nice to finally get some balls to find some gaps and hit the ball out of the park," Maybin said.
Jim Miller relieved Millwood and got the final two outs of the inning.
Millwood allowed seven runs -- six earned -- and nine hits. He struck out one.
Maybin is hitting .372 against the Rockies. Three of his nine home runs have come against Colorado. ... Tulowitzki has missed six straight games and eight of the past 10. Helton has missed six consecutive games and 12 of the past 14. Gonzalez missed his fourth game in a row. ... Padres INF Jesus Guzman (sore neck) was not in the lineup. ... The Padres will send RHP Mat Latos to the mound against Colorado RHP Jhoulys Chacin in the second game of the series Tuesday.