Was it the black-and-white jerseys? Maybe they thought Brook Lopez was Robin. Or were most of them Knick fans? For whatever reason, five Nets got booed Friday night when they were shown on the big screen at Barclays Center Friday night as the Islanders took the ice for the first time in Brooklyn.

Brook Lopez, Chris McCullough, Bojan Bogdanovic, Markel Brown and Rondae Hollis-Jefferson were adorned in personalized Islanders new black-and-white jerseys, which many of the Islander faithful hate ... but which Brett Yormark told CNBC is now the NHL's top-selling gear.

The Islanders lost 3-2 in overtime to the Stanley Cup champion Chicago Blackhawks. John Tavares, appropriately enough, scored the first Islander goal in the new building.

As expected, the arena drew mixed reviews, a lot of the negative ones about obstructed views in a building that was once described as "basketball-centric.".

Ok, 10 minutes into the first period of the first game at a new building, and here is one side of the stands. #Isles pic.twitter.com/wTO3fH4lg0 — Brett Cyrgalis (@BrettCyrgalis) October 10, 2015

This guy paid $75 for obstructed view #IslesOpeningNight seats behind main entrance goal at #BarclaysCenter pic.twitter.com/tNCvRUr9xn — Rich Calder (@Rich_Calder) October 10, 2015

.@BarclaysCenter has some obstructed views for #Islanders games. It also has some of the best seats in @NHL http://t.co/Y6D49kGYhh via @WSJ — Alex Raskin (@alexraskinNYC) October 3, 2015

There were also complaints about the ice...

Told one #Isles player ice looked like a giant slushy from the press box. "That's the correct word to use," he said. "Awful," another said. — Arthur Staple (@StapeNewsday) October 10, 2015

And there were the usual complaints about fans showing up late, just as they do for the Nets. Hey, it's New York and according to Barclays Center execs, most of the season ticket-holders are from the city, not Long Island.