NEW YORK — Count the knockdowns: five.

Count the titles: two.

Conor McGregor became the first UFC fighter to simultaneously wear two belts when he picked apart lightweight champion Eddie Alvarez with punches to the head and rolled to a second-round knockout victory at UFC 205 before adoring masses at Madison Square Garden early this morning.

“Where’s my second belt?” Ireland’s personable McGregor asked in the octagon as it was not immediately available.

McGregor (21-3) sized up Alvarez (28-5) immediately and dropped him with blows thrown from his left hand three times in the first round.

Alvarez failed to produce an effective response, missing kicks and failing to find a reversing McGregor with punches until the featherweight champion surged forward and looked for openings again.

“You’ve got to have size, length, some attributes … if you don’t I’ll rip your head off,” McGregor said, and after fighting his two fights before Saturday’s at the welterweight limit of 170 pounds he boasted, “I’ll slay everybody in the company.”

McGregor finished the assault at the 3 minute, 4 second mark of the second round. He had knocked down Alvarez earlier in the second before planting a hard punch on the jaw and following that with a blast to the right ear to send the former champion to the canvas.

“I’d like to apologize, to absolutely nobody,” McGregor said, a nod to Alvarez’s Thursday news conference warning that he needed one from McGregor or he would make him pay for it.

UFC stacked the card with three title fights that were expected to help set a gate record of more than $17 million at MSG. The 1999 boxing match between Lennox Lewis and Evander Holyfield drew a record $13.5 million.

On Saturday night, Tyron Woodley’s big punches won him the best round of his title defense against Stephen “Wonderboy” Thompson and allowed him to retain his welterweight belt.

By the thinnest of margins.

Woodley (16-3-1) keeps the title by virtue of a majority draw as judges scored the fight 47-47, 47-47, 48-47 in the co-main event.

“We will do it again,” said Thompson (13-1-1), who landed the more effective punches of the fifth round.

Joanna Jedrzejczyk successfully defended her UFC women’s strawweight championship with a unanimous decision win over Karolina Kowalkiewicz.

Also, Miesha Tate, who played a pivotal role in the women’s division rise to prominence in UFC, announced her retirement inside the octagon following a loss to Raquel Pennington. The 30-year-old Tate says the loss played a role in her decision.

“I had a lot more to give but I couldn’t pull it out of myself,” she said.

Tate (18-7) defeated Holly Holm in March to win the bantamweight title and then lost the belt in her first title defense to Amanda Nunes in July.