Justin & Taylor Surprise Concertgoers with Duet

Looks like Justin Bieber finally made good on his promise to "stop in" on Taylor Swift in concert!

Back in July Bieber heard that Taylor covered one of his hits during a show in Toronto prompting the Canada native to take to Twitter and write "heard you sang BABY at your concert in TO. thank u for the love ... might have to come by and stop in on a show."

Last night the pop idol followed through surprising fans at Swift's L.A. concert at the Staples Center with a duet of Bieber's hit song Baby.

After the show ended, Swift tweeted "You think you've heard LOUD screaming in your life.. Then @justinbieber comes out and does a surprise song during your show. Woah. Unreal."

The duet was such a hit, Bieber hinted at another round saying: "@taylorswift13 we should do that more often. :) great show! #muchlove."

Swift will be in Los Angeles for three more shows for her Speak Now tour at the Staples Center this Wednesday, Saturday and Sunday.