Oramas allowed a broken-bat single with one out in the ninth inning, fanning nine over 8 1/3 innings as Lake Elsinore defeated Lancaster, 1-0.
Oramas (2-0) retired the first 25 batters on 90 pitches for the Storm (26-13), who were looking for the first no-hitter in franchise history and the first perfect game in California League since 1999.
The 20-year-old left-hander was loaned by the Padres last year to the Mexican League, where he finished 9-1 with a 2.31 ERA in 25 games and won the league's Rookie of the Year award. He began 2010 with Class A Fort Wayne, posting a 0-1 record with a 1.20 ERA and 25 strikeouts in 15 innings.
"He had a live fastball, he elevated the fastball effectively and he had an above-average curveball," Storm manager Carlos Lezcano said. "He didn't use it much, but it was effective when he did. He was outstanding, a very good job.
"He threw the pitch he wanted, and the guy hit it over the shortstop's head, broke his bat and got a hit out of it," Lezcano added of Brandon Barnes' single.
The former Major Leaguer also had high praise for his squad, which has won seven in a row and 18 of the last 21 games.
"The players are coming together very well, the starting pitching has really turned it on as of late," Lezcano said. "Our bullpen has been outstanding all year, and we have some guys with speed who can run. Everything's clicking for us right now. It's a bunch of guys who know how to win and they are doing it."
The single by Barnes set up a dramatic ninth, as the JetHawks had runners on the corners with one out against closer Brad Brach, who struck out Jay Austin and retired Albert Cartwright on a fielder choice to earn his league-leading 16th save.
The Storm picked up a run in the first against Lancaster starter Dallas Keuchel (1-3). Drew Cumberland, Daniel Robertson and Vincent Belnome singled to open the frame, and Cumberland scored on Cody Decker's double play.
Keuchel was the hard-luck loser for the JetHawks, who have lost seven straight. He struck out 11 and allowed one run on six hits over eight innings.