As soon as Ryan Garcia makes weight Friday for the 140-pound title shot at his amateur rival and WBC champion Devin Haney, a flood of ticket buyers are expected to rush windows and their phone apps and sell out Brooklyn’s Barclays Center.

“By the weekend, the place is gonna be packed,” a ticket broker told BoxingScene. “They’re definitely going to fill it up, 100 percent.”

Getting there, however, has been a harrowing ride. Days into the formal promotion of Haney-Garcia, those connected to its ticket sales were plagued by sinking hearts.

Instead of making the greatest volume of tickets available – the $150 and $250 “cheap seats” – Golden Boy Promotions withheld them from pre-sale and on-sale buyers.

“It made no sense,” said one veteran ticket broker who observed the strategy from a distance. “Ultimately, your best advertising tool is the person who bought a ticket. Four, five guys buy it, they tell their buddies and then those guys buy … .

“It’s when you don’t release the cheap seats that you have guys saying, ‘Are you going to the fight?’ ‘No, I’m waiting.’ ‘OK, I’ll wait, too.’ You get behind the eight ball … and especially at Barclays, where [Premier Boxing Champions] is always slashing prices at the last minute. The culture there is the fans are used to waiting.”

But then Garcia, almost immediately, went unhinged, refusing at the Hollywood news conference to answer Haney and his father/trainer/manager Bill Haney asking whether he would even show up on fight night while his Golden Boy stablemate and co-main participant Arnold Barboza was floated as a possible replacement.

“By saying Barboza could be the backup … people are like, ‘So, if we buy a ticket and Ryan’s not fighting, who’d we buy a ticket for? We’re not spending this for Haney-Barboza!’” said the broker, speaking on the condition of anonymity because their work occasionally includes transactions with boxing promotions.

“Golden Boy had spent all this money on the press conference in New York and then Los Angeles and then your two cheapest price ranges, you don’t even sell to the public,” the broker noted. “You had a press conference that clearly worked because of all the eyeballs on it, but a lot of people – maybe 60 percent – are going to want the cheapest ticket and you’re holding it back. Just a bad way of running it, unfortunately.”

The only seats available in those first days ranged from $300 to $800, and Garcia’s instability was only worsening as he followed the bizarre news conference in which he discussed drinking alcohol and smoking weed with an onslaught of disturbing comments and behavior featured on a social-media account that has boosted him amid the antics to 10.5 million Instagram followers.

‘When they mispriced it at the start, people waited, and then – let’s be honest – Ryan Garcia has basically made people not want to buy because they were afraid he’s going to back out … ,” the broker said.

“With Ryan’s behavior, the market really stopped. The buyers stopped to wait. Think about it: If you’re a fan of his from California and you’re thinking about flying to New York, are you really going to do it? The videos of him training in his living room. We’ve already seen how this ends thanks to [Julio Cesar] Chavez Jr. 

“The lull they went through is because of what Ryan has done.”

Rather quickly, however, Golden Boy effectively adjusted by opening sales for the cheap seats and lowering prices for many floor seats.

And even though second-time title challenger Garcia has continued behaving with volatility – on Tuesday, for instance, he got slapped in the face by Haney atop the Empire State Building after repeatedly asking the WBC 140-pound champion, “Where’s your mom, b****?” – it appears now he will answer the first bell.

Bill Haney said he’s tried to turn a blind eye to Garcia’s crazed activities, chalking it up to an influencer’s work and believing fight night will become a special evening for his champion son.

“The opportunity to be in front of New Yorkers, that’s everything. It’s why we hit New York. It was a great opportunity,” Bill Haney said.

“Ryan hasn’t been the best dance partner, but we have the best place in the world to perform. Being the king in New York, that means everything.”