Justin Timberlake's two year 20/20 World Tour is coming to a close in the near future, and he's beginning to pull out all the stops including guest appearances during his shows.

Repost from @GarthBrooks Whoa. Whoa. Whoa. So... Yes. This happened.

A video posted by Justin Timberlake (@justintimberlake) onDec 12, 2014 at 11:40pm PST

Last week Jay-Z joined him at the Barclays center, and last night one of JT's idols joined him in Nashville. Garth Brooks came on stage with Justin and performed 'Friends in Low Places.'

With Garth's recent re-entry into country music, he's been breaking his own ticket sales records for his upcoming tour and making more appearances. This surprise sing-along with Justin Timberlake leads me to believe there may be plenty of surprises ahead for both artists.

Speculation is ripe that Justin and his wife Jessica Biel are expecting their first child, and we know family is the reason that Garth decided to take such a long break from the music business. He wanted to raise his own kids. Will Justin do the same? He waited six years between his last two albums.

It will be interesting to see what's in store for them both.