It’s a Clash of the Pop Titans at the top of the chart, as Bruno Mars goes #4-to-#1, grabbing the pole position from P!nk. But this win is somewhat tainted in that “When I Was Your Man” was sale priced at 69 cents last week at the iTunes Store—so maybe it deserves an asterisk. The most dramatic surge came from the cross-genre teaming of Florida Georgia Line and Nelly (the latter no stranger to these parts), as sales on the remix of “Cruise” were up by a considerable 372%. Also picking up steam was Macklemore & Ryan Lewis’ “Can’t Hold Us,” the follow-up to “Thrift Shop,” with +37%.

1. Bruno Mars, “When I Was Your Man” – 340k
2. P!nk f/Nate Ruess, “Just Give Me a Reason” – 280k
3. Florida Georgia Line f/Nelly, “Cruise” (remix) – 248k
4. Macklemore & Ryan Lewis, “Thrift Shop” – 211k
5. Rihanna f/Mikky Ekko, “Stay” – 207k
6. Macklemore & Ryan Lewis, “Can’t Hold Us” – 186k
7. Imagine Dragons, “Radioactive” – 163k
8. Justin Timberlake f/Jay-Z, “Suit & Tie” – 145k
9. Icona Pop f/Charli XCX, “I Love It” – 131k
10. Pitbull f/Christina Aguilera,” Feel This Moment” – 124k

Just outside the Top 10 was Demi Lovato’s “Heart Attack,” which moved another 116k, settling at #11, edging Justin Timberlake’s “Mirrors, with 115k, while Fall Out Boy’s “My Songs Know What You Did Last Night” stayed at #13 with 100k on the nose. [HitsDailyDouble]