LaLiga president Javier Tebas believes Barcelona will play Girona in Miami despite the Spanish FA (RFEF) requiring more documentation over the plan.
The proposal, part of a new deal with Relevent, the company behind the International Champions Cup, had chosen the January fixture as the first LaLiga game to be played in the United States.
Players have voiced their opposition to the plan despite Girona and Barcelona giving the green light to move the match to Miami.
And the RFEF appeared to put the proposal in jeopardy on Friday by writing to LaLiga to ask for more details on the agreement.
"What we are being asked now is for more documentation and that is what I will prepare," Tebas said in response.
"I have been with the Delegate Committee all morning and I have not been able to study this letter, which is quite long, we are going to look and prepare everything.
"I am still quite optimistic on all of the issues and we will have to see what happens in the end."
RFEF leader Luis Rubiales has made it clear he opposes the Relevent deal, which he has described as an "invasion" of the United States.
Tebas, though, feels he can convince Rubiales to give the RFEF's blessing to the 15-year deal with Relevent, citing the relocation to Morocco of this season's Supercopa de Espana between Barca and Sevilla.
"He [Luis Rubiales] is not saying no," he added. "But asking for more documentation to be able to resolve any legal issues. Obviously, they do not have much desire, but I am still an optimist.
"There is a precedent of already having played a game in Tangier. We will work on what is asked of us, but I'm surprised that the letter keeps referring to FIFA when [Gianni] Infantino can have his opinion, but it has no place in the regulatory procedure."
|Khabib holds talks over Mayweather Moscow fight|
|Wolf in for Titz as Hamburg try to stop slump|
|Davies released from Wales squad as Evans comes in|
|Mbappe on track to match Messi and Ronaldo, says Giuly|
|Coleman, Kipchoge and Lyles among IAAF Male World Athlete of the Year shortlist|
|Serena Williams will win slams again sooner or later, says Seles|
|You always want the best – Ter Stegen open to Neymar return|
|Xavi: My teams will never use Mourinho´s style|
|I knew what I got myself into - LeBron appreciates Lakers are a work in progress|
|Mourinho: Ronaldo loves United but he will want to score|
|Cooper completes Rebels move and takes parting shot at Reds coach Thorn|
|Bellerin amazed by ´born champion´ Ozil|
|Penguins, kangaroos and ´Stone Cold´ Steve Austin: Halloween comes early for Trail Blazers|
|Ronaldo gunning for United, Aguero targets double record - Champions League in Opta numbers|
|Ill Vardy couldn´t stomach penalty decision – Puel|
|LeBron´s Lakers lose again, Magic stun Celtics|
|Bartomeu: No Barca return for Neymar, Valverde contracted until 2020|
|Simmons and ´stimulating´ 76ers in NBA Finals mix, says Longley|
|Falcons heap further misery on Giants|
|Vidic hails Ronaldo as ultimate professional ahead of Old Trafford return|
|Warriors´ Cousins nearing NBA return|
|Pogba can´t do the basics – Souness criticises Man United star|
|Messi absence big blow for Barca as Icardi talks up Inter|
|´You can´t cry, that´s true´ – Ronaldo responds to Isco|
|Bartomeu: Barca still competitive without Messi|
|Bills RB McCoy remains in concussion protocol|
|Raiders place Marshawn Lynch on IR|
|Emery calm over title talk after another Arsenal win|
|Green: Warriors have to clean up defensively|
|Mariners say Bolt talks ongoing amid reports contract offer was rejected|
|Proud captain Ozil revels in Arsenal´s ´sexy football´|
|Puel angry over Holding handball|
|Cilic breezes through in Basel, Anderson fights back|
|Ingram: Four-game ban better than we expected|
|Raiders send Cooper to Cowboys for first-round pick|
|Arsenal 3 Leicester City 1: Outstanding Ozil inspires comeback win|
|World Series 2018: Three reasons why the Dodgers will win|
|Yarmolenko out for six months after Achilles surgery|
|World Series 2018: Three reasons why the Red Sox will win|
|Ozil eclipses Klinsmann to become Premier League´s most prolific German|
|Allegri expecting Old Trafford battle against Mourinho´s United|
|Bertens feared she did not belong in Kerber clash|
|Returning Ronaldo expecting ´tough´ game against Manchester United|
|Cristiano Ronaldo confident of clearing his name amid rape allegation|
|Osaka looking to learn from losing start in Singapore|
|Kovac expects tough test against AEK Athens|
|Whyte gives Chisora deadline over rematch|
|Spartak Moscow sack Massimo Carrera|
|Atletico Madrid confirm fresh injury issue for Gimenez|
|Dolberg extends Ajax contract after Real Madrid links|
|Ronaldo an example for Lukaku to follow|
|Bertens battles back to blast past Kerber|
|Ramos apologises for training ground fracas|
|Raikkonen should take heed of Alonso misfortune as F1 career winds down|
|Guardiola wants Manchester City fans to push team to Champions League glory|
|Isco not interested in departed Ronaldo - he didn´t want to be here|
|World Series 2018: Three storylines to watch in Red Sox-Dodgers|
|Neymar focus bad for football - PSG´s Maxwell|
|Marco Ianni charged by FA over Jose Mourinho touchline row|
|Stephens sees off Osaka in see-saw Singapore battle|
|I´m happy at Manchester United - Mourinho dismisses Real Madrid reports|
|Semenya and Asher-Smith head IAAF Female World Athlete of the Year shortlist|
|Mandzukic to miss Manchester United trip|
|I turned down Manchester United to return to Juventus - Bonucci|
|Sanchez out of Manchester United´s clash with Juventus|
|Australia make Short work of run chase in T20 win|
|Brotherly g-love! Tommy Fury follows Tyson into the pros|
|Ozil´s international retirement can help Arsenal - Emery|
|If you sack Lopetegui, you have to sack us all – Isco|
|Lopetegui defiant amid Real Madrid sack reports|