Katy Perry and Lady Gaga, two of today's biggest pop music stars, have both released new singles in the past week, creating a battle for top sales which makes fans everywhere wonder who will come out on top.

Perry's single, "Roar" was released for digital sale on Aug. 12 and is currently number one on the iTunes sales chart. Lady Gaga's single, "Applause," which was available for purchase a day later than Perry's song, is close behind at number four, behind Robin Thicke's "Blurred Lines," and Avicii's "Wake Me Up."

The total number of sales for both singles will be released tomorrow, Aug. 21. According to Billboard, it would not be surprising if both songs ended their first week of sales with 500,000 purchases each.

If "Roar" and "Applause" sell more than 400,000 copies each, it would be the first time two songs debuted in the same week and sold more than 400,000 copies. It would also become the first non-holiday week in over a year with such high sales. This last happed May 5 of last year with Maroon 5's "Payphone" (493,000) and Gotye's "Somebody That I Used to Know" (463,000).

"Roar" is the first single from Perry's fourth studio album Prism, which Capital Records is scheduled to release Oct. 2. "Applause" is Lady Gaga's opening single from her fourth studio album, (excluding remix albums) ArtPop, which Streamline/Interscope will release Nov. 11.

This competition is expected to affect the MTV Video Music Awards which will take place Aug. 25. Both Perry and Gaga will perform their new singles live for the first time ever.

By the time of the performance, the ladies will know their place on Billboard's Hot 100 list. This is sure to give the ladies some incentive to create stellar VMA performances to best the other and claim the crown of the queen of the charts.