Britney Spears' guest appearance on "How I Met Your Mother" fetches its highest rating ever

Britney Spears' guest appearance on How I Met Your Mother Monday night, March 24, fetched the CBS sitcom its highest rating ever.

The episode earned a 4.5 preliminary rating among adults aged 18-49, reports The Hollywood Reporter.

The show which averaged 10.7 million viewers, up from last week's 9.7 million, was the fourth highest rated show of the evening.

While the rating boost could be attributed to hype and curiosity, the appreciation from critics was well deserved by Britney who was facing a camera after a long time.

Britney last faced the camera during the MTV Video Music Awards, when she sleep walked through her gig.

"Britney the Trainwreck showed how she can still be Britney the Performer," wrote the Associated Press.

"Spears proved she can act every bit as well as she can sing," wrote the New York Daily News.

"Brit looked slim, (OK she was behind a desk), trim and gorgeous," wrote the New York Post.

Despite the kudos, Britney may not appear on TV again because she needs a controlled environment on the set, something other producers may not be able to guarantee.

In which case, the confidence boost from her successful appearance on HIMYM will hopefully aid her recovery process.

"Acting won't be a usual thing for Britney. She really needed this, though," A source told MSNBC. "For her it was like a taste of her old life, but it was a taste that was very carefully planned. This wasn't about her career, it was about her health."