Pics: Most Awkward On-Stage Celebrity Bombs

Last year, The Situation proved that writing jokes isn't as easy as it looks during Comedy Central's "Roast of Donald Trump," suffering boos for his jokes about The Donald's hair and marriage. At the end of his set, comedian Jeffrey Ross jumped in to take some of the heat off the reality star, showing his belly and saying, "They call me The Saturation."

Earlier this year, Tracy Morgan ("30 Rock") came under fire when he went on an anti-gay tirade during a Nashville gig and his words went viral. Tracy joked about how he would react if one of his son's were gay, saying, "[he] better talk to me like a man and not in a gay voice or I'll pull out a knife and stab that little n**ger to death." Tracy quickly held a press conference apologizing for the comments, saying, "I don't believe that anyone should be bullied or just made to feel bad about who they are. I totally feel that, in my heart, I really don't care who you love, same-sex or not, as long as you have the ability to love. ... To err is human, to forgive is divine."

The man famous for playing Jerry Seinfeld's "hipster doofus" neighbor Cosmo Kramer, tried his hand at standup in 2006, eight years after "Seinfeld" went off the air. During a performance at the Laugh Factory in Los Angeles, Richards spiraled into a racist rant directed at a few unruly audience members, screaming, "Throw his ass out. He's a n**ger! He's a n**ger!" Richards later made a public apology on the "Late Show with David Letterman," but America didn't seem to accept.

Although the platform was small, Christina was on one of the biggest stages in the world when she mixed up the words to the National Anthem during the most watched Super Bowl ever. During Super Bowl XLV, the Grammy winner sang "What so proudly we watched at the twilight's last gleaming," instead of "O'er the ramparts we watched, were so gallantly streaming." "I took in the moment a little bit too much," the singer told Ellen DeGeneres, suggesting that she was overwhelmed by the honor of performing at such a huge event. "Shoot me for appreciating the moment."

In 2004, the pop star was so embarrassed after being caught lip-syncing on "Saturday Night Live" that she awkwardly abandoned the stage, causing the show to abruptly cut to commercial. The following year, Simpson returned to the sketch show with a triumphant performance of "Catch Me When I Fall," a song inspired by her "SNL" snafu.

Being a performer is just like any other job - you have some good days and you have some bad days. The only difference is that when a celebrity has a bad day, everyone knows! Click through to take another look at some of the most memorable train wrecks of recent years.