Nathan Buckley packs on the PDA with girlfriend Brodie Ryan before serenading her on the mic at her karaoke-themed birthday bash

Nathan Buckley has never been shy about publicly praising his girlfriend Brodie Ryan.

So it's no surprise that the AFL legend, 51, packed on the PDA with the brunette beauty during her surprise 35th birthday bash at Melbourne's Crown Casino on Friday evening.

At the karaoke-themed party, all the guests got on the mic to vent, including Buckley, who serenaded Brodie with Roy Orbison's Pretty Woman.

Brodie shared a video of the romantic moment on Instagram, saying: “Just a beautiful woman serenaded by her love.”

In the clip, the former footy star put his arm around Brodie's shoulder and pulled her close as he performed the classic rock song.

Brodie shared a video of the romantic moment on Instagram, saying: 'Just a beautiful woman serenaded by her love'

At one point, the pair even joined forces to perform Cher's If I Could Turn Back Time as a duet.

Gushing about the surprise party on social media, Brodie wrote: “Thank you to my beautiful partner.”

She continued, “You make me feel special every day, but last night was next level.”

Brodie was joined at the party by a handful of famous friends, including Bachelor star Zoe O'Brien and Justin McKeone, the ex-husband of model Olivia Molly Rogers.

Brodie's birthday party isn't the first time Buckley has praised the brunette business manager.

The happy couple posed with two friends at the lavish party

'I feel very fortunate to have met a partner in Brodie who I love and respect. Life is good,” he told the Herald Sun in September.

Brodie seems to have settled into the role of a WAG well, as the brunette beauty has undergone an incredible makeover to match her new life with Nathan.

She went from a blonde girl-next-door look to a bronzed glamazon almost overnight after dating the former AFL player and coach.