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."
|Calleja axed as Villarreal coach|
|Kenyan Drake on Miami Miracle: I couldn´t let Gronk tackle me!|
|Ronaldo: I deserved Ballon d´Or, the numbers don´t lie|
|Rugby Australia to make Cheika decision this month|
|England defender Gomez signs new Liverpool deal|
|Ronaldo wants to see Messi follow him to Italy|
|Neymar happy to play in any position for PSG - Draxler|
|Paine insists he is ´fine´ after taking blow to finger|
|Ponzio: River players will be ´idolised´ for Libertadores success|
|Champions League permutations: How Inter, PSG and Liverpool can progress|
|Kohli: India were better and deserved to win|
|Bears shut down Goff, Rams|
|India survive dramatic finish against Australia|
|Klopp calls for electric Anfield atmosphere against Napoli|
|Saints clinch back-to-back NFC South titles, Bears trump Rams|
|Bucks improve to 2-0 against Raptors with win in Toronto|
|Black Caps include Patel for Sri Lanka Tests|
|Maidana: River want Real Madrid clash|
|Cowboys top Eagles in OT behind stellar Cooper display|
|AC Milan evaluating Fabregas signing – Leonardo|
|WATCH: Steelers´ chance at game-tying field goal slips away|
|Hayne will plead not guilty to charges, says lawyer|
|Boca boss Schelotto: The only thing I feel is sadness|
|Cardinals´ Fitzgerald makes NFL history with most receptions for one team|
|River Plate´s Copa Libertadores star Gonzalo Martinez confirms January departure|
|Klopp: I was never worried about Salah´s form|
|Packers QB Rodgers sets NFL record for most passes without an interception|
|World Cup bulking hampered Man United form – Lukaku|
|Leonardo rules out Ibrahimovic Milan return|
|Warriors´ Green to return against Timberwolves|
|I feel for him… we´ll make it work – Butler responds to Embiid´s frustration|
|Torino draw no missed opportunity for misfiring AC Milan, claims Gattuso|
|We´ll always be linked together forever - Wade reflects on playing with James before final match-up|
|O´Sullivan wins record seventh UK title|
|Chiefs secure playoff berth, Saints win NFC South|
|River Plate 3 Boca Juniors 1 (aet, 5-3 agg): Quintero and Martinez clinch Libertadores title in extr|
|WATCH: Chiefs QB Mahomes throws no-look pass|
|Dolphins defeat Patriots on miraculous final play|
|Kizzire eagle snatches QBE Shootout victory|
|AC Milan 0 Torino 0: Donnarumma shines, Cutrone misses late chance|
|Back to the drawing board for West Indies - Chase|
|Copa Libertadores: Messi and Griezmann among stars in Madrid for River-Boca Superclasico|
|Brady sets NFL record for most career TD passes|
|Copa Libertadores: Tevez named on Boca bench for Superclasico final|
|Premier League needs VAR, right now! - Benitez fumes over Dean´s decisions|
|McCall expects Itoje to fit for the Six Nations|
|Solari salutes Real Madrid character after ´ugly´ Huesca win|
|Berbatov defends under-fire Lukaku|
|Sarries crush Blues to maintain unbeaten start|
|Newcastle United 1 Wolves 2: Doherty punishes Yedlin red with late winner|
|Deeney jokes he´ll ´smash´ former Watford star Richarlison|
|Huesca 0 Real Madrid 1: Bale ends drought as Solari´s men edge to victory|
|Ponting: Umpires not looking at no-balls|
|Bale ends longest LaLiga goal drought|
|Porter backs Brees for MVP, Saints for Super Bowl|
|Verstappen eyeing 2019 title fight|
|Wall ´shouldn´t have played´ against Cavaliers after scoring just one point|
|Hazard: Man City the best team in the Premier League despite Chelsea win|
|LeBron explains why he gave a Grizzlies employee his game-worn shoes|
|Bangladesh cruise to ODI victory as seamers punish Windies|
|Football will win over violence, claims CONMEBOL president|
|Alcorcon support Reus Deportiu over unpaid players|
|Saponara explains cheeky celebration after last-gasp leveller|
|Godin and Filipe Luis return to Atletico training|
|Kick It Out condemns alleged racist abuse of Sterling|
|Emotional Oosthuizen clinches South African Open title|
|The Sunday Seven - 7 Key Opta facts for NFL Week 14|
|Martino salutes Atlanta´s grand plan|
|India´s tail must show greater application - Bangar|
|Mourinho: Diogo Dalot can be new Gary Neville|