UNIONDALE, N.Y. — Seanie Monaghan pined for this — a big homecoming fight on Long Island and a massive leap in class.

The 35-year-old fighter, who was undefeated after feasting on club fighters as a local ticket-seller, found out he couldn’t hang on the top level.

Marcus Browne, a 2012 Olympian and THE RING’s No. 9 light heavyweight, made easy work of Monaghan in the Fox co-feature on Saturday with a second-round stoppage in an utter mismatch.

Browne (20-0, 15 KOs) dropped Monaghan early in the opening frame with a straight left, and it was easy work throughout.

Monaghan (28-1, 17 KOs) was on unsteady legs after the knockdown, but a low blow helped him escape the round.

No matter, Browne, 26, finished what he started in Round 2, and banged Monaghan around the round on the ropes, seemingly landing every shot, until referee Steve Willis mercifully ended the contest at :40.

Photo by Ed Diller / DiBella Entertainment

“I could tell that I hurt him, but I didn’t want to rush and walk into anything,” said Browne, a native of Staten Island. “I just took my time and allowed everything to fall into place.

“I’m honored and blessed to be a part of this event and I just want to move upwards and onward from here. I want a date with Adonis Stevenson next.”

That won’t come next, though. Stevenson owes a long overdue mandatory title shot against countryman Eleider Alvarez. But with Browne steadily improving — his jab was impressive and a real weapon — the bout makes sense for some time next year.

“It was an honor for me to represent Long Island. I knew that it was a big task tonight. Marcus is even faster than in sparring. I’ll be alright though, I’m happy to lose to a guy the quality of Marcus Browne.

“Marcus has always been a fast starter. He always comes out very fast. I thought I was ready for the speed, but he is very skilled. I think he’s going to go a long way.”

Browne might, but he’s going to have to prove it against much better competition. And that’s exactly what he wants.

Photo by Ed Diller / DiBella Entertainment

Undercard report by Vladimir Lik: In front of a raucous Polish crowd, Brooklyn’s Adam Kownacki earned the signature win he’s been searching for by defeating former world title challenger and fellow Polish heavyweight Artur Szpilka by fourth-round TKO.

Kownacki (16-0, 13 knockouts) landed a massive overhand right hand to send Szpilka down for the first knockdown. Szpilka beat the count but clearly had not recovered. Kownacki jumped on Szpilka to land a succession of three unanswered blows prompting referee Arthur Mercante Jr. to step in and stop the bout at 1:23.

Szpilka had the faster hands but Kownacki’s punches carried more weight both literally and figuratively. Kownacki let the gloves fly with the full weight of 242 pounds behind them outweighing Szpilka by nearly 20 pounds.

Szpilka found some success in the second round with his jab, which swelled up both of Kownacki’s eyes, but Szpilka had no answer for Kownacki’s bruising right hand which found a home each time.

In the fourth round Kownacki bullied Szpilka into the ropes and unloaded the big right hand that ultimately hurt Szpilka for good. This was Szpilka’s first bout since suffering a nasty one-punch knockout by WBC heavyweight champion Deontay Wilder in January 2016.

And now, with two knockout defeats in a row, it’s unclear where Szpilka goes from here.

Patrick Day upset Eric Walker (15-1, 8 KOs) in an entertaining back-and-forth 10-round bout by scores of 96-93, 96-93 and 95-94.

Day (14-2-1, 6 KOs) dropped Walker in the fourth round and controlled the action thereafter. This marks Day’s third consecutive win since being stopped by Carlos Hernandez in 2015.