More than two million people watched the CNN talk show debut of Piers Morgan -- but even the draw of an interview with Oprah Winfrey was no match for Sarah Palin on rival Fox News.

CNN said on Tuesday that 2.099 million people watched "Piers Morgan Tonight" on Monday -- a 219 percent increase on the average audience for veteran Larry King's previous show in that spot.

But the Fox News show "Hannity", which featured an interview with Tea Party favorite Sarah Palin, drew 2.3 million viewers, according to ratings data.

Morgan, an ebullient British former newspaper editor and reality TV judge, was appointed last year to replace King at CNN, which has lost audiences in recent years to its more partisan left and right-wing rivals at MSNBC and Fox News.

U.S. critics gave a mixed reception to his first outing, with some blasting his fawning approach to Winfrey, and others giving him high marks for energy and enthusiasm.

"The end result wasn't so much an interview as a chat, which fell flatter than people might have expected. It did, for all the world, seem like two self-important rich people talking to each other," said the Hollywood Reporter.

Entertainment Weekly's Ken Tucker said the first show -- in which Winfrey revealed she had contemplated suicide when she became pregnant at age 14 -- "revealed host Piers Morgan to be clever, tenacious, vain, a flatterer, and fitfully funny".

New York Times critic Alessandra Stanley said that after all the bullish hype about Morgan being unpredictable and even dangerous, Monday's debut was "probably too timid."

Time magazine's James Poniewozik said it was too early to tell how successful Morgan will be in raising ratings for CNN. Others hoped for more sparks in his encounters later this week with British comic Ricky Gervais and radio shock jock Howard Stern.

"At least (CNN) is doing it with someone who approaches the job with relish, and understands that it's better to be disliked than to be ignored.

"When Morgan's first week of interviews is over...his challenge will be to make sure he can keep not just his guests but the rest of us talking," Poniewozik said.