Justin Bieber surprise 2014 Coachella performance with Chance the Rapper

Justin Bieber shows surprises the crowd for a surprise performance with Chance The Rapper on day 3 of the 2014 Coachella Valley Music & Arts Festival on April 13, 2014 in Indio, California.

Kevin Winter/Getty Images

Justin Bieber played the main stage at Coachella.

Okay, well, technically he performed for a single song, and as a surprise guest during the performance of Chance The Rapper, a buzzed-about indie MC with no proper album to his name yet. But technicalities aside, Bieber was there, white bucket hat and black tee, on the Coachella stage for the first time. And it wasn't even that surprising.

COACHELLA 2014: FULL COVERAGE

Justin Bieber Joins Chance The Rapper

Bieber's appearance came on Sunday afternoon, hours after Beyonce made a cameo during her sister Solange's set to dance out to "Losing You." Bieber also followed Gwen Stefani, who played her solo pop smash "Hollaback Girl" during Pharrell Williams' guest star-laden hits parade. Katy Perry had been spotted taking in another Coachella weekend long before Bieber and Chance combined for "Confident." And once Bieber concluded his cameo, his buddy Drake was still on deck, getting ready to stop by Jhene Aiko's evening set to run through “From Time.’

Coachella 2014!
JUSTIN BIEBER CHANCE THE RAPPER
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FULL COACHELLA COVERAGE

This year was hardly the first Coachella to boast occasional cameos from mainstream stars -- Perry has been a Coachella fixture for years, Rihanna stopped by the Indio fest in 2012 to guest with Calvin Harris, and R. Kelly took the stage during Phoenix's headlining set last year. Surprise performers aside, however, pop music was engrained into the 2014 Coachella Valley Music & Arts Festival lineup, arguably more than ever before. Ellie Goulding, Pharrell Williams, Lorde, Foster The People, Bastille, Aloe Blacc, Lana Del Rey, Calvin Harris, Capital Cities… all of these artists can claim recent mainstream moments, and each of them contributed to the feeling that the longtime alternative mecca was slowly shifting gears. Every hour or two, it seemed like another Top 40 hit was wafting across the polo grounds -- and that's not even counting the hour in which Girl Talk mashed them all together.

COACHELLA LIVE ON STAGE PHOTOS

Contributing to Coachella's subtle pop makeover was the general feeling that rock music was being shrugged off by this year's festivalgoers. The crowd for EDM upstart Martin Garrix's Friday night performance dwarfed that of post-punk legends the Replacements, who were playing their first West Coast show in 22 years and did so in front of a few hundred people. Superchunk similarly soldiered through an under-attended performance, entertaining a half-empty Gobi tent while Rudimental blasted its international hits to an overflowing crowd in the adjacent Mojave tent. Performers like Muse, Queens of the Stone Age and AFI lost huge chunks of its audiences to catchier concurrent sets from Skrillex, Empire of the Sun and Bastille, and when Arcade Fire's Win Butler took a shot against the lack of "bands still playing actual instruments at this festival" during the band's headlining set, the line felt like a territorial jab at the shifting nature of the festival, which sounded a lot different when Arcade Fire headlined three years earlier.

COACHELLA BACKSTAGE PHOTOS

One month after the emerging artists that played this year's South By Southwest festival were forced to coexist with Lady Gaga and Pitbull, this year's Coachella often felt like the little guys were being edged out by the pop behemoths. At the same time, however, the 2014 festival was home to an unusually high number of alternative artists that had just happened to find a gateway to mainstream audiences over the past few months. How could festival bookers forecast the out-of-nowhere Top 10 hits by Bastille, Capital Cities or Aloe Blacc when the lineup was being cobbled together? Lorde told her sizable audience that she was booked for Coachella 2014 in May of 2013 -- months before anyone in the U.S. knew that she had never seen a diamond in the flesh. Perhaps this year's Coachella actually underlined how much pop music has bended toward alternative music over the past year, with Top 40 radio pairing party hits by Miley, Gaga and Katy with offbeat singles like "Royals" and "Pompeii."

Likewise, most of the pop-leaning artists booked at this year's festival have reached new career peaks in the months leading up to Coachella. Pharrell was always going to be one of the bigger draws at this year's festival, but his performance turned into even more of an event when "Happy" became the most inescapable song of 2014's first quarter. Ellie Goulding was similarly expanded her profile over the past year thanks to a string of recent hits like "Burn" and "I Need Your Love" to bundle with her 2012 breakout "Lights." Even Lana Del Rey, who conjured a crowd as cultish as a Beyonce audience, never had anything resembling a pop radio single before Cedric Gervais' remix of "Summertime Sadness" unexpectedly took hold last year. It's not like Coachella booked a slew of established pop performers for its 2014 bill; instead, a handful of artists have recently grown into that category, and their audiences responded in kind.

So the pop takeover of this year's Coachella was all happenstance, right? Not exactly. Let's face it: Coachella has a "cool factor" that few U.S. music events have been able to duplicate, and an amount of media coverage that only a few festivals can also boast. Set in the gorgeous California desert just a few hours south of Hollywood, Coachella remains a posh experience of music absorption, the first major summer festival of each year, and a destination that attracts celebrities and, thus, eyeballs. How many of Chance The Rapper's other festival performances will Justin Bieber attend this summer after Coachella? Likely none. As long as Coachella maintains that glossy appeal and ability to get people talking, the pop sphere will try to puncture it, as it successfully did in 2014.