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 Sunday morning.

“Where’s my second belt?” Ireland’s personable McGregor asked in the octagon as it wasn’t 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 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’d 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.

McGregor pounced and referee John McCarthy waved the bout off.

“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’d make him pay for it.

Alvarez was instead the one who paid dearly, as his title reign is in one defense.

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.

But Woodley knocked down Thompson twice in the fourth round.

The two staged a classic five minutes as the heavy-handed Woodley, in his first title defense, twice found Thompson on the jaw with punches and sought a decisive choke.

“I did want to finish it,” Woodley said.

Thompson escaped, however, reversed and began landing punishing punches atop Woodley as the horn blew.

To start, Woodley achieved a superior position atop Thompson in the first round, landing punches to the head and side, depriving the taller challenger from advantages in a stand-up fight while bloodying him with furious blows at the end of the round.

Thompson remained standing in the second and landed clean punches, mixing in a reverse kick to the mid-section that backed Woodley. And in a deliberate third, he landed the better blows again.

In the first of three title fights on the card, Poland’s Joanna Jedrzejczyk defeated countrywoman Karolina Kowalkiewicz by unanimous decision on three scores of 49-46 to successfully defend her women’s strawweight belt for the fourth time.

The depth of Jedrzejczyk’s talents shined in building an early lead, as her ability to land punches, kicks and knees flustered a game Kowalkiewicz challenge. Jedrzejczyk landed a head kick and reverse elbow in the final minute of the second round.

Kowalkiewicz (10-1) rallied in the fourth and landed hard punches that backed the champion across the octagon floor to the cage, where she took on more punishment.

“I wasn’t hurt, but … Polish girls are the toughest in the world,” Jedrzejczyk said. “I knew it’d be tough.”

Although both sides of her face puffed badly at the end, Jedrzejczyk (13-0) out-struck Kowalkiewicz, whose ability to make it a fight against the dominant champion impressed the crowd.

Also on the pay-per-view portion of UFC 205, former women’s bantamweight champion Miesha Tate retired after her upset loss by decision to her former “The Ultimate Fighter” reality television series student Raquel Pennington of Colorado.

“It’s not my time anymore,” said Tate, who lost her belt to Amanda Nunes in July. “It’s because of the result.”

Pennington, en route to her fourth consecutive victory (by scores of 29-28, 30-27, 30-27) outworked Tate and landed effective jabs on the No. 1 contender Tate.

Former middleweight champion Chris Weidman, a New Yorker who helped lobby state officials to legalize the sport after it was banned in its lightly regulated days, had his homecoming spoiled when he was knocked out 24 seconds into the third round by Cuban Yoel Romero.

Romero earns a title shot at middleweight champion Michael Bisping after he hammered Weidman in the head with a flying left knee, dropping Weidman and finishing him with two punches to the head.

Afterward, Romero told Bisping, who was in attendance, “You see the real champion.”

Second-ranked lightweight Khabib Nurmagomedov improved to 24-0, bolstering his chances for a title bout, with a third-round submission choke of sixth-ranked Michael Johnson.

“No question, I deserve my shot,” Nurmagomedov said.

Former lightweight champion Frankie Edgar of New Jersey also enhanced his title consideration in the featherweight division.

Edgar responded to a July loss to former featherweight champion Jose Aldo by defeating seventh-ranked Jeremy Stephens by unanimous decision.

Edgar recovered from a knockdown by head kick in the second round to take down Stephens repeatedly and applying some time-chewing choke attempts.