On Tuesday evening, after the season finale of “The Voice,” Christina Aguilera celebrated her 33rd birthday (one day early) with boyfriend Matthew Rutler.

The two were seen leaving Off Vine, a popular American cuisine restaurant in Hollywood. According to E Online, the American singer and songwriter wore a long black skirt, matching heels, and sexy silver top. Rutler donned a blue sweater with leather jacket, jeans, and black and red sneakers.

Though Christina first denied dating the production assistant, who worked on her movie, “Burlesque,” they are now officially a couple.

In October 2010, Christina filed for divorce from her husband, music executive Jordan Bratman. they have a son, Max, who was born in 2008.

Before the intimate birthday celebration, Christina performed her first duet with Lady Gaga during “The Voice” finale.

She is such a powerhouse vocalist and I was honored to join the stage with @ladygaga tonight on #TheVoice! xo

— Christina Aguilera (@xtina) December 18, 2013

Gaga seemed to be a fan of finale contender Jacquie Lee before the show.

Been catching up on THE VOICE, I love @jacquieleemusic Beautiful girl with a beautiful voice! Vote for her monsters http://t.co/vOfYgJI1iJ

— Lady Gaga (@ladygaga) December 17, 2013

Though Lee was runner-up, Tessanne Chinn was crowned the winner of the reality singing competition last night.

Since turning 32 last December, Christina has landed two Top 10 singles on the Billboard Hot 100.

http://www.youtube.com/watch?v=yRd8D1ll7_U

Image via Facebook