NEW YORK -- Cardi B, in her well-known silly demeanour, "opened" the 2018 Video Music Awards -- not with a performance, but with cute jokes.

The new mom was onstage Monday at New York's Radio City Music Hall pretending to hold a baby, but she then revealed to the audience that it was actually a Moonman, which she won earlier in the night for song of the summer for her No. 1 hit, "I Like It," with Bad Bunny and J Balvin.

IN PHOTOS: 2018 MTV Video Music Awards

The rapper was the top contender of the night with 10 nominations. She gave birth to Kulture Kiari Cephus last month and is up for video of the year with "Finesse," her collaboration with Bruno Mars. The song's video, inspired by the 1990s sketch comedy series "In Living Color," is also nominated for four other honours.

For the top prize, Cardi B and Mars was competing with Childish Gambino's "This Is America," Drake's "God's Plan," Beyonce and Jay-Z's "Apes--t," Camila Cabello's "Havana" and Ariana Grande's "No Tears Left to Cry." (Most of the top nominees -- including Drake, Beyonce, Jay-Z, Mars and Gambino -- weren't expected the VMAs.)

Nicki Minaj won the first televised award -- best hip hop -- and checked comedian Tiffany Haddish for dissing girl group Fifth Harmony, now on hiatus.

After congratulating ex-Fifth Harmony Camila Cabello on her five nominations, presenter Haddish said sarcastically, "Hi Fifth Harmony." When Minaj accepted an award moments later, she looked to Haddish and said, "Don't be coming for Fifth Harmony because Normani is that (chick)." Normani currently has her first hit apart from the group with the Khalid-assisted "Love Lies."

Minaj, who has been a trending topic this week after she madly tweeted about why her new album debuted at No. 2 behind Travis Scott, also provided the first bleeped moment of the night when told the audience to listen to her Apple Music radio show this week to hear "who the (expletive) of the day award is going to."

There was a political moment when Logic was joined onstage by young immigrants wearing T-shirts that read, "We are all human beings," to protest the Trump administration's separation of migrant children from their parents after they illegally crossed the U.S.-Mexico border. The rapper, best known for the suicide prevention anthem "1-800-273-8255," wore a T-shirt that read, "(Expletive) the wall."

Shawn Mendes was the night's first performer, and rocked the stage with a performance of "In My Blood." Other performers were to include Ariana Grande, Travis Scott, Minaj, Maluma and Post Malone, who won song of the year for "Rockstar."

"Thank you to my family, thank you to my crew ... This is sick," he said.

Grande won best pop video and thanked her fiance Pete Davidson "for existing."

Jennifer Lopez, who will receive the Michael Jackson Video Vanguard Award for lifetime achievement, was also expected to hit the stage. MTV also plans on honouring Aretha Franklin, who died last week from pancreatic cancer at age 76.

As for the top nominees, Beyonce and Jay-Z were behind Cardi B with eight bids for "Apesh--t," filmed at the Louvre museum in Paris. Gambino's "This Is America," which tackles racism and gun violence, earned him seven nominations, while Drake, who gave away $1 million dollars to Miami residents in his "God's Plan" clip, scored seven nods.

Mars, who has six nominations, was up for artist of the year alongside Cardi B, Drake, Post Malone, Cabello and Grande.

Taylor Swift was shut out of the major categories but did nab three nominations for technical awards: Her No. 1 hit, "Look What You Made Me Do," is up for best art direction, best visual effects and best editing.

Cardi B's other nominations include best new artist, best hip-hop video for "Bartier Cardi" and best Latin video for "Dinero" with Lopez and DJ Khaled.

Others nominated for multiple VMAs include SZA, Ed Sheeran, Janelle Monae, Khalid, Alessia Cara and Dua Lipa.

Avicii, who died in April, is nominated for best dance and best visual effects for "Lonely Together," which features Rita Ora.