Eminem, the "Rap God," and Rihanna, the hot "Stay" and "Umbrella" singer, added new tour dates to their "Monster" tour. Eminem Twitter followers hear new Rihanna dates. The presale of the Eminem Rihanna tour 2014 has put Facebook in a frenzy, just like Rihanna put Eminem in a daze in their latest music video collaboration.

Eminem took to Twitter to announce "NYC/DET/LA this August with @Rihanna! #TheMonsterTour." Rihanna quickly retweeted Eminem's tweet, adding, "OH IM THERE!!!!!"

Eminem and Rihanna know about the upcoming tour of three US cities in that starts in August. But the tour is getting bigger. An additional show has been added to the Rihanna Eminem tour 2014 at each date. That means that "The Monster" tour is currently six shows long.

Eminem and Rihanna have added one more tour dates to their anticipated "Monster" tour. Eminem and Rihanna are only playing New York, LA and Detroit, Eminem's hometown, but duo have added an additional date to each city. Eminem and Rihanna will perform at Los Angeles' Rose Bowl on August 7 and 8, at New Jersey's MetLife Stadium on August 16 and 17 and at Detroit's Comerica Park on August 22 and 23.

Live Nation told the Detroit Free Press that the additional Eminem Rihanna Tour dates were added because of high ticket demand during this week's pre-sale campaign. The original tour dates held a pre-sale on Friday. MLive said it caused a "frenzy" on Facebook when the Tickets.com sold out in just 14 minutes after the tickets went on sale. Fans can purchase tickets to the Rihanna Eminem tour 2014 shows at TicketProcess.com.

Eminem and Rihanna added a second Comerica Park show to their Detroit concert engagement, on Aug. 23, one night after their already-announced show at the downtown stadium. Second nights also have been added to their Monster Tour stops in Los Angeles (Aug. 7-8) and New York (Aug. 16-17).

Eminem and Rihanna fans will surely hear the duo's latest collaboration. The hit song, "The Monster." RiRi and Slim Shady will also perform their mega-hit "Love The Way You Lie" from 2010. Eminem and Rihanna also collaborated on album tracks "Love The Way You Lie (Part II)" and "Numb."

Tickets for the Detroit shows will run you between $49.50-$159.50. Full sales start at 10 a.m. Friday. For the Aug. 23 date, American Express cardholders can buy tickets starting at 10 a.m. Saturday

According to Nielsen SoundScan, Eminem's latest album "The Marshall Mathers LP 2" sold another 13,000 copies in the week ending March 16. That means all of Eminem's albums have now each sold more than 2 million.