CLEVELAND Two of Donald Trump's toughest primary rivals, Marco Rubio and Ted Cruz, spoke at his nominating convention Wednesday but opted not to offer full-throated endorsements. The arena erupted in jeers and boos as Cruz finished his remarks and the crowd realized he was not endorsing the nominee who invited him to speak. "Endorse him!" "We want Trump! We want Trump!" Cruz only once mentioned Trump's name, and Rubio in a video clip mustered no enthusiasm for Trump beyond calling him a better choice than Hillary Clinton. "After a long and spirited primary, the time for fighting each other is over. It's time to come together and fight for a new direction for America," Rubio said. The night was supposed to be vice presidential nominee Mike Pence's first, big opportunity to introduce himself to the nation. Instead, the Cruz controversy overshadowed Pence. Appearances by the men Trump used to call "Lyin' Ted" and "Little Marco" underscored the lingering uncertainty over the GOP's unconventional new standard-bearer. While convention delegates have shown unity and energy in attacking Clinton — "Lock her up!" has emerged as the convention's anthem — speaker after speaker has tip-toed around the nominee. The extraordinary scene of anger against Cruz filling the basketball arena also showed Trump's uncanny knack for producing drama. Nominating conventions are typically painstakingly choreographed with speeches vetted and revetted before delivery. The reality star's four-day convention has been an unpredictable affair punctuated by an unexpected and unsuccessful rebellion by anti-Trump Republicans, controversy over Melania Trump lifting speech lines from a Michelle Obama speech and then Cruz's high-profile snub. "He showed an unprecedented level of self-interest," Miami-Dade GOP chairman Nelson Diaz said of Cruz. "I think he ended his career here. Coming here to promote himself and not support the nominee was disgusting. It was a new low. A very new low." It was not immediately clear whether the Trump campaign knew no endorsement would come from Cruz. Late Wednesday, Trump tweeted: "Wow, Ted Cruz got booed off the stage, didn't honor the pledge! I saw his speech two hours early but let him speak anyway. No big deal!" Florida delegate George LeMieux said, "If you're going to speak at someone else's convention, you have to support them. If you don't want to do that, stay home. I have never seen people so angry as they were about Sen. Cruz's speech tonight. People who probably liked him, maybe not as their first choice, were seething." Until the Cruz uproar, the most rousing moment of the night came when one of the few well-known speakers wholeheartedly behind Trump, conservative radio host Laura Ingraham, called out former Trump rivals who had signed a pledge to endorse the eventual nominee. "Donald Trump has pledged to work tirelessly to get our country back on track," she said. "I want to say this very plainly, to all of you boys with wounded feelings and bruised egos: We love you, but you must honor your pledge to support Donald Trump now. Do it tonight." Cruz and Rubio, both potential leading candidates for president in 2020, offered the bare minimum. "I'm aggravated. I'm angry. I'm mad," Illinois delegate Aaron Delmar said in an interview on the convention floor. "He had an opportunity to unify the party and do the right thing . . . and he chose to take a coward's way out and not support Donald Trump. Donald Trump was not my candidate, but we went through what's called democracy. We had 17 candidates, and now we have one nominee." Cruz, he added, is "a total hypocrite and I think they should start a new group called Never Cruz." Brian Ballard, a lobbyist who works with Trump and a top Republican fundraiser, lashed out on Twitter: "Ted Cruz may be the worst human to ever serve in the US Senate. A horrible wretch hated by his colleagues and reviled by his citizens." Pence gave a forceful speech in his own measured manner, stressing his faith and vouching for the harder-edged nominee. The crowd at one point broke into "We like Mike" chants. He mixed in some self-depricating humor, saying Trump was "a man known for a large personality, a colorful style. . . . I guess he was just looking for some balance on the ticket," said the mild-mannered Pence. "For those of you who don't know me, well, which is most of you . . . I'm a Christian, a conservative and a Republican, in that order." Pence has denounced negative campaigning, a stark contrast to his running mate, but he vouched for Trump's decency. "Now I'll grant you he can be a little rough with politicians on the stage. And I'll bet we see that again. But I've seen this good man up close, his utter lack of pretense, his respect for the people who work for him and his devotion to his family." Pence spoke of Trump as a fighter who never quits and who until this week had been fighting mostly alone. "This week, with this united party, he's got back up," Pence told the gathering that looked united only in its hostility toward Clinton. "Make America First Again" was the theme of the convention's third night, and it had a distinctly Florida flavor with speeches from Gov. Rick Scott and Attorney General Pam Bondi, as well as Rubio. "Lock her up — I like that," Bondi said of the spontaneous crowd chant that has repeatedly erupted this week. Other speakers included son Eric Trump, former U.S. House Speaker Newt Gingrich and Wisconsin Gov. Scott Walker. "Last August, I said that any of the Republicans running would be better than Hillary Clinton," said Walker, one of the first candidates to end his primary campaign last year. "I meant it then, and I mean it now. So let me be clear: a vote for anyone other than Donald Trump in November is a vote for Hillary Clinton." Gingrich, who had been a finalist to be Trump's running mate, tried to throw Cruz a lifeline, noting that the Texas senator had called for Republicans to back the candidate who will uphold the Constitution. "To paraphrase Ted Cruz, if you want to protect the Constitution of the United States, the only possible (choice) is the Trump-Pence ticket." The Trump-Pence ticket got off to an awkward start amid reports that Trump had second thoughts and considered changing his mind. At their first joint appearance, Trump spoke for 28 minutes before bringing Pence to the stage. But Pence, the Indiana governor and conservative former member of the U.S. House, has helped reassure many Republican politicians uneasy with Trump. Florida Agriculture Commissioner Adam Putnam, who served with Pence in Congress, said his style could hardly be any different than Trump. "He'd be about 180 degrees different," Putnam said. "Mike Pence is a level, steady, consistent guy who is a well-read, conservative rooted in sort of the founding philosophical documents of conservatism. While he is a former Democrat, he was a Democrat at one point in his life, it was studying Ronald Reagan and studying the premises of conservatism that brought him into our party." Times Washington bureau chief Alex Leary contributed to this report. Contact Adam Smith at [email protected] Follow @adamsmithtimes.