Bobby Portis’ stellar play in his first career postseason start ignited a Milwaukee fan base desperate for a trip to the Finals.

There was no way Bobby Portis Jr., stepping into injured teammate Giannis Antetokounmpo’s gaping spot in the Milwaukee Bucks’ starting lineup Thursday night, was going to seriously take the Greek Freak’s place or match his production. That’s a job too big for pretty much anyone, not just on the Bucks roster but across the NBA.

Now, if Portis gets to bring along his 16,389 buddies at Fiserv Forum the way he did in Milwaukee’s 123-112 victory over Atlanta in Game 5 of the Eastern Conference finals, then there’s a chance.

A very good chance, frankly, as evidenced by Portis’ 22 points, eight rebounds, three assists and three steals in the first playoff start of his six-year NBA career. And as valuable as Portis was on the floor, logging nearly 36 minutes with Antetokounmpo (hyperextended knee) limited to sideline enthusiasm, Portis was even more so in the arena.

His sudden rise as a fan favorite, heading rapidly toward some sort of Milwaukee folk hero, was evident in the crowd’s chants — “Bob-BY! Bob-BY!” — and remarkable in the way they responded each time Portis flexed in celebration of a big play.

Whenever he would smile or mean-mug or otherwise exhort fans along the sideline or baseline, or trudge back onto the court after running in his high-motor hustle past the basket stanchion, you’d almost think he was one of those fans, their delegate at least, playing in and enjoying the moment.

“Milwaukee’s a tough city,” Portis said. “Some people at the start of the season, they were telling us all about the city and how tough it is to live here and things like that, and you know, the city goes through a lot. So when they see somebody that gives his all and works hard … it’s a blue-collar city and I’m a blue-collar player.”

With a T-shirt under his jersey, a head band up top and that slightly stiff, straight-up way he runs, Portis looks like he might have wandered in from the downtown YMCA. Add to that the emotions readily available on his face and the dirty work he often does with all the rough edges showing, and it’s clear: People love and name kids after Antetokounmpo. They can admire the sleek physicality of Khris Middleton or Jrue Holiday, and marvel at Brook Lopez’s gargantuan size. But they feel, they connect, with Portis.

“I’m going to [take] the shots whether they are going in or not,” Portis said. “I still give my all to the team 100 percent for the name in front of the jersey, and they love players like that. It’s just fun, man, to go out there and play this game, and … just get them involved just so we can have that home-court advantage.”

Milwaukee truly had no wiggle room heading into Game 5 without its best player. The Hawks didn’t have their young star Trae Young either, but Atlanta already had beaten the Bucks on Thursday without Young and with Antetokounmpo around for 24 minutes before he got hurt.

On Friday, Milwaukee’s second, third and fourth most important players acted like it, each dialing up his intensity and aggression. Holiday probed and attacked Atlanta’s defense while getting into each man he defended. Middleton looked for his shot, sure, but also for openings to deliver the ball. Lopez, as he had a few times already this postseason, seemed to flow knowing he wasn’t crowding Antetokounmpo’s turf in the lane. He played more forcefully at both ends than he had all year.

Combined, those three accounted for 84 points, 26 rebounds, 21 assists, five steals and five blocks, while making 33 of 58 shots. Terrific production – except it wasn’t going to be enough. That’s where Portis came in.

There were his 22 points. His eight rebounds and two steals. His activity defensively with the Bucks switching constantly. Most of all, there was his zeal.

“I think his passion is infectious,” Bucks coach Mike Budenholzer said. “His teammates love him. The fans love him. He brings that passion for the game, for life. He’s fun to be around. I think the crowd can feel that. His teammates can feel that. Coaches can feel it.

“He’s a worker, too. So I think it’s a little bit of everything, but passion to me is the thing he brings to the game.”

Said Holiday: “He brings this energy that nobody else could bring. It doesn’t matter how he’s playing, but he’s going to muck it up, he’s going to fight, he’s going to talk, and everybody loves when somebody talks. He knows that we got his back.”

A native of Little Rock, Ark., who played two years at the University of Arkansas, Portis’ first time living out of state came after the Chicago Bulls made him the No. 22 pick in the 2015 Draft. His everyman qualities and those now-famous “crazy eyes” made him a hit with United Center crowds, too, but that dash of Kevin Garnett intensity didn’t stop the Bulls from trading him to Washington in February 2019.

He signed as a free agent five months later with the New York Knicks — pre-Tom Thibodeau resurgence — which explains the gap in Portis’ playoff resume from the first round with Chicago as a rookie to the 13 games he has played for the Bucks in this run.

Portis got dropped from Budenholzer’s rotation in the final three games against Brooklyn in the conference semifinals. But he got encouragement from Antetokounmpo afterward, telling him he’ll be needed. Neither man imagined opportunity would come quite the way it did Thursday.

Portis still is only 26. He has a player option this offseason, and salary cap limitations — and the market he has created for himself with his recent play — might have him moving on again.

But for now, Milwaukee is Portis’ home-court advantage.

“Coming here was one of the best decisions for my career,” he said. “I started my career kind of shaky, up and down, a lot of highs, a lot of lows. And when you first come to the NBA, you don’t really understand the journey. I was the best player on my team, Player of the Year, All-American, so when I first got to the league, I wasn’t playing a lot. Didn’t really understand and kind of lost myself a little bit, but I fought my way in. Played some. Went through a lot of altercations and things like that.

“But the journey is what makes it sweet, man, in the NBA. You really can’t put a tab on that.”

The next test might be bigger, if Budenholzer comes knocking again before Game 6 Saturday in Atlanta (8:30 ET, TNT). Portis will have his teammates’ backs again, but he’ll have to do it at State Farm Arena without the 16,389 who had his in this one.

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Steve Aschburner has written about the NBA since 1980. You can e-mail him here, find his archive here and follow him on Twitter.

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