San Sebastian (Spain), Second-division side CD Mirandes showed Real Sociedad how they reached the semifinals of the Copa del Rey, forcing the hosts to work hard for a 2-1 win that sets the stage for an exciting second leg next month in Miranda de Ebro.

While hardly impressive in league play, Mirandes have proven to be the giant-killers of the 2020 Copa del Rey, dispatching three LaLiga clubs, including fifth-place Sevilla, to reach the final four.

And the visitors got off to a fast start at San Sebastian's Reale Arena on Thursday, where Martin Merquelanz -- who plays for Mirandes on loan from Sociedad -- forced a stop from home goalkeeper Alex Remiro in the opening minutes, reports Efe news.

But the hosts got on the scoreboard first. 

Christian Portu drew a foul in the box from Mirandes defender Odei and the referee awarded a penalty. Mikel Oyarzabal converted to put La Real up 1-0 in the eighth minute.

Undaunted, Mirandes remained on the attack, led by Merquelanz, and managed to pull level in the 39th minute when Mickael Malsa got the ball to Aias, whose shot deflected off Sociedad defender Nacho Monreal and out of Remiro's reach to make it 1-1.

The stars appeared to be in alignment for Mirandes as Sociedad lacked pace and struggled with self-inflicted wounds.

With three minutes left in first-half regulation, Martin Odegaard tested Mirandes keeper Limones, who made the initial stop and turned aside a second effort by Portu before conceding to the Norwegian on the rebound.

Sociedad pushed hard for a third goal after the restart, yet aside from a Portu strike that forced an outstanding save from Limones, Mirandes looked the more dangerous team.

Alex Isak, who scored a brace in Sociedad's 4-3 quarterfinal upset of Real Madrid, had a sub-par night and was pulled in the 66th minute for Willian Jose, greeted by jeers from supporters still sore over after failed bid to move to Tottenham Hotspur during the January transfer window.

Jose delivered a great ball to Oyarzabal shortly after coming on, but the striker fumbled the chance, while Remiro dealt with a free-kick from Merquelanz to preserve the narrow lead.