PHILADELPHIA – Kristaps Porzingis knows what losing is like.

The 7-foot-3 Knicks rookie was immersed in it last season in the Spanish League with Sevilla, leading to an in-season firing of head coach Scott Roth, so he feels for Sixers center Jahlil Okafor.

The two top-four picks battle for the first time in a regular-season game Friday night at Wells Fargo Center. The Sixers are 1-25 and on pace to break the NBA’s futility record set by the 1972-73 Sixers (9-73).

Many have blamed the losing for Okafor’s unseemly off-court incidents. He went from winning an NCAA championship at Duke to the NBA’s bottom.

“That would be tough,’’ Porzingis said Friday at the Knicks morning shootaround. “That’s basketball sometimes. Losing like that is very tough. I’ve been on a losing team last season, the first part of the season. It’s really tough. The negativity is always there. It’s not a good feeling. You mentally grow as you go through those tough times.’’

Porzingis has it much better, and must be extremely thankful the Sixers passed on him at No. 3 so he could fall into Phil Jackson’s lap. The Knicks president surrounded Porzingis with veterans, and the Knicks are way ahead of last season’s disgrace – the most-beloved 12-14 squad in New York City sports history.

“I’m in a really good situation,’’ Porzingis said. “Having veterans around me to help me out on and off the court. He’s in a tough situation. I’m sure he’ll find a way to make his team win and get better as a player and how to be smarter off the court.’’

Okafor has bounced back with panache since his two-game suspension for the alleged street fights and a speeding incident. Okafor missed the first Knicks meeting Dec. 2 at the Garden because of the suspension.

“I’m pretty excited,’’ Porzingis said. “The first time I didn’t get to play against him because he was out. It’s first time since summer league. I think it will be fun.’’

Porzingis, Okafor and Karl-Anthony Towns have become the rookie Big 3 of frontcourt talents, set to be compared for the next 10 to 15 years.

“I don’t try to measure myself against those guys,’’ Porzingis said. “We’re just trying to do our best for our individual teams, not trying to compete with each other, but obviously I’m following how they’re doing and they’re probably following how I’m doing. I’m happy those guys are putting up numbers.’’

In Las Vegas, Porzingis was the starting center for the Knicks summer league squad and matched up against Okafor, who is averaging 17.8 points and 8.1 rebounds as a bullish low-post machine.

Porzingis blocked Okafor’s shot three times – the first major sign the European was more than a project. Knicks coach Derek Fisher plays Porzingis at power forward, but with center Robin Lopez’s productivity slipping, the Latvian is starting to get more minutes at the 5.

“I was playing the whole game against him,’’ Porzingis said. “Whenever coach wants me to play the 5, I’ll play the 5 and try to stop him.

“He’s a very good offensive player. His post game is a really high level. It’s hard to stop him in the post. My strategy is to front him and be running around him so he couldn’t receive the ball. Once he receives it, it’s really hard to stop him. But I tried to use my length to block his shots.’’

Porzingis got to know Okafor a little during the draft process and in Las Vegas. He said he’d like to “exchange numbers’’ with him Friday night.

Porzingis has seven blocks Wednesday night against Towns and the Timberwolves, but he is amid a four-game shooting slump (10 of 39). He’s not getting the putback dunks that marked his first few weeks. Teams have adjusted.

“I think so – people are looking out for me, boxing me out first,’’ Porzingis said. “Somebody’s putting a body on me. Nobody likes to get dunked on. They’re focused more on boxing me out. A lot of times that’s how I get my putbacks, running from the outside, and there’s more focus on boxing me out.’’

Knicks rookie point guard Jerian Grant has been a DNP the last two games, and played just three minutes the contest prior in Sacramento. Fisher made an unfortunate comparison for the first-round rookie.

“Lou Amundson has been in this league 10 years and he doesn’t get to play,’’ Fisher said.

Grant said he needs to get the second unit “more organized.’’