Britney Spears came extremely close to snagging the leading role in the movie “The Notebook.”

Hollywood casting director Matthew Barry told the Daily Mail that the then 21-year-old pop star’s 2002 audition for the role of Allie “blew us all away” — and that she very nearly got the part in the 2004 film.

A newly released video of her audition shows Spears breaking down in tears.

“Our jaws were on the floor,” Barry said. “I was blown away. Absolutely blown away. She brought her A-game that day.”

The role of the 1940s heiress who falls in love with Ryan Gosling’s Noah ultimately went to Rachel McAdams.

Fans have long known that Spears, now 41, filmed a screen test for the romantic drama, based on Nicholas Sparks’ 1996 novel.

But Barry went even further to say that the “Toxic” singer, whose largest screen role has been in the film “Crossroads,” was in the top tier of candidates, beating out actresses such as Scarlett Johansson, Claire Danes, Kate Bosworth, Amy Adams, Jaime King and Mandy Moore.

The casting director also unveiled her two-decade-old emotional audition tape, which Spears buffs have been begging to watch for years, in which she emotionally performs Allie’s “I prayed for you to die in the war” monologue. In the clip, the young actress begins to sob.

“Britney wasn’t just good — she was phenomenal,” Barry told the Mail. 

Still, in her upcoming memoir “The Woman In Me,” out Oct. 24, Spears said she does not regret losing the coveted role to McAdams. 

“‘The Notebook’ casting came down to me and Rachel McAdams,” Spears wrote. “And even though it would have been fun to reconnect with Ryan Gosling after our time on ‘The Mickey Mouse Club,’ I’m glad I didn’t do it.”

As for “Crossroads,” Spears revealed that method acting took over while she was on set.

“My problem wasn’t with anyone involved in the production but with what acting did to my mind. I think I started method acting — only I didn’t know how to break out of my character,” she explained in an excerpt obtained by People last week.

“I really became this other person. Some people do method acting, but they’re usually aware of the fact that they’re doing it. But I didn’t have any separation at all. I ended up walking differently, carrying myself differently, talking differently,” she continued. “I was someone else for months while I filmed ‘Crossroads.’ Still to this day, I bet the girls I shot that movie with think, She’s a little … quirky. If they thought that, they were right.”