Arsenal and Cardiff City unite for an emotional tribute at the Emirates over the tragic Emiliano Sala situation. (0:42)

Seat cushions likely to have come from the plane carrying missing Cardiff City footballer Emiliano Sala have been found, the Air Accidents Investigation Branch said on Wednesday.

The cushions were discovered Monday on a beach in France near Surtainville on the Cotentin Peninsula by French authorities.

"From a preliminary examination, we have concluded that it is likely that the cushions are from the missing aircraft," the AAIB said in a statement.

Investigators said they now planned to launch an underwater seabed search for aircraft wreckage. Due to weather conditions, the search would start at the end of this weekend and take up to three days.

"Based on a detailed assessment of the flight path and last known radar position, we have now identified a priority search area of approximately four square nautical miles," they said.

A remotely operated vehicle will be used to examine visually any wreckage found.

Later on Wednesday, Sala's former club Nantes paid him tribute in Ligue 1 match against St Etienne, their first match since he went missing.

Referee Frank Schneider stopped play in the ninth minute -- in a possible reference to Sala's shirt number -- for a minute of applause during which Nantes coach Vahid Halilhodzic was pictured in tears.

Fans unveiled banners for Sala, most notably a giant Argentinian flag, and all of Nantes' players had Sala's name on the back of their shirt.

A portrait of Sala was unfolded on the centre circle as the players stepped onto the pitch to chants of "Emiliano Sala" from fans.

The Nantes players wore a t-shirt saying "On t'aime Emi" (We love you Emi) and the St Etienne players had t-shirts saying "Pray for Sala."

"It was a very special night, we played more for him than for us," Nantes defender Diego Carlos said after the 1-1 draw. "We gave everything for him."

Sala, 28, remains missing after an aircraft carrying him vanished from radar on the way from France to Wales on Jan. 22. Rescuers ended their search for the forward and pilot David Ibbotson three days later.

Guernsey harbour master David Barker said at the time the chances of finding survivors were "extremely remote," and in a statement, he said next of kin had been informed of the decision to end the search. Following a crowdfunding campaign, the search for the pair was reopened on Jan. 27.

Cardiff and Arsenal paid tribute to Sala ahead of their match at the Emirates Stadium on Tuesday.

After the match, which Arsenal won 2-1, Cardiff defender Sol Bamba said some of the team's players were afraid to fly following the disappearance of record-signing Sala.

"It is very difficult to even describe," Bamba said. "It is very unusual, a big tragedy. We have all been affected by it, the lads, the city, the whole club.

"I think we needed something like this, the game, to get underway so we're back as normal, if I can say [that]. But it was a very difficult week.

"We travel ... by plane, and some of the lads have been thinking, 'I don't want to go on it anymore.' It was that deep."

Information from Reuters was used in this report.