International Tennis Federation spokeswoman Heather Bowles confirmed to the AP on Tuesday that Carlos Ramos was chosen to work at the best-of-five series between the countries that begins Friday and concludes Sunday in Zadar, Croatia.
The U.S. team includes Jack Sock, Sam Querrey, Steve Johnson, Mike Bryan and rookie Frances Tiafoe.
Ramos was in the chair at Flushing Meadows last Saturday when Naomi Osaka won her first Grand Slam title by beating 23-time major champion Williams 6-2, 6-4. That match descended into chaos — with thousands of spectators booing and both players crying during the trophy ceremony — after Williams confronted Ramos about his rulings.
Williams, a 36-year-old American, was fined a total of $17,000 by the U.S. Open's tournament referee the next day for three code violations.
On Monday, the ITF, which oversees the Davis Cup, issued a statement defending Ramos, saying his "decisions were in accordance with the relevant rules" and that his rulings were "reaffirmed by the U.S. Open's decision to fine Serena Williams for the three offenses."
"Ramos undertook his duties as an official according to the relevant rule book and acted at all times with professionalism and integrity," the ITF statement added.
The governing body's support for Ramos came after the WTA, which operates the women's tour, was critical of the way things went between him and Williams in New York.
"The WTA believes that there should be no difference in the standards of tolerance provided to the emotions expressed by men vs. women and is committed to working with the sport to ensure that all players are treated the same," the tour's CEO, Steve Simon, said in a statement. "We do not believe that this was done last night."
Williams was cited by Ramos for getting coaching signals; for breaking her racket, which automatically cost her a point because it was her second code violation of the match; and for calling Ramos a "thief," which cost her a game because it was her third code violation.