Diego Chaves remains delayed in his native Argentina, jeopardizing Saturday’s welterweight appearance against Brandon Rios at the Cosmopolitan of Las Vegas, Top Rank Promotions’ Bob Arum informed RingTV.com on Monday.

Arum said the situation has resulted from a backlog within the United States Immigrations system stemming from a computer malfunction which has delayed thousands of visa applications.

Junior welterweight Jose Zepeda (19-0, 16 knockouts) would be chosen to replace Chaves if the visa issue is not resolved by Tuesday, said Arum.

“The issue is not with Chaves but it’s with a worldwide f–kup with the state department with their computer going down. There’s backlog now of three quarters of a million visas that they can’t get their website working to process and for these visas to be released. There are hundreds of thousands people in China waiting for their tourist visas and it’s a mess. So we’re giving it until tomorrow to see if there’s a change,” said Arum.

“Now, if Chaves can get his visa by tomorrow, then we’re okay. But if not, we’re going to substitute this kid who is on the card and this Mexican kid, Zepeda will take his spot. So there will be a fight but it will be beyond our control as to whether it’s Chaves or not. But it’s not Chaves’ problem. The visas been approved and he’s been trying to get it for 10 days. But the point is that it’s not a Chaves situation but it’s a worldwide state department problem. It’s really disgraceful.”

BoxingScene.com first reported the development.

Rios (31-2-1, 23 knockouts) is 1-2 with one knockout in his past three fights and is coming off a unanimous decision loss to Manny Pacquiao in his welterweight debut in November.

Chaves (23-1, 19 KOs) would be fighting on American soil for only the third time. He debuted in Las Vegas with a six-round unanimous decision over Edvan Dos Santos Barros at the Hard Rock Hotel in March 2010.

Zepeda, 25, is coming off a unanimous decision over Robert Frankel in April that ended his streak of 12 straight stoppage victories.

ISAAC CHILEMBA TO FIGHT CORY CUMMINGS ON SERGEY KOVALEV-BLAKE CAPARELLO CARD

South African light heavyweight Isaac Chilemba (22-2-2, 9 KOs) will face Baltimore’s Cory Cummings (17-6-1, 13 KOs) in support of Sergey Kovalev’s defense of his WBO 175-pound title against Blake Caparello from the Revel Casino Hotel in Atlantic City, Main Events announced on Monday.

“We signed Isaac Chilemba with a plan in mind for him in the light heavyweight division,” said Main Events CEO Kathy Duva. “Seeing how he does against a brawler like Cory Cummings is the next step. I’m sure Cummings will try to upset our plans, so the fans in attendance at Revel on Saturday are in for another great light heavyweight fight.”

STEFAN HAERTEL TO MAKE PRO DEBUT ON AUGUST 16

German amateur star Stefan Haertel, 26, will make his professional debut against super middleweight Olegs Fedotovs (18-14, 12 KOs) on August 16 at the Erfurt Exhibition Hall in Thuringia, Germany, Sauerland Events announced on Monday.

“After many successful years as an amateur, I am looking forward to this new challenge,” said Haertel, a Berlin-based prospect who signed with Sauerland Events in May. “It has been six months since my last competitive fight and I can’t wait to get back into the ring, shake off the rust and show everyone what I am capable of.”

Haertel is training with renowned German coach Karsten Roewer.

“Super middleweight is currently one of the most exciting divisions in the world,” said Chris Meyer, CEO of Sauerland Events. “We believe Stefan has the ability to go right to the top. That is why we are matching him with such an experienced opponent in his first professional fight.”