Aitor Karanka's side stormed to a 6-2 victory over fellow relegation candidates Mallorca last time out, while the visitors played out a goalless stalemate with Valencia.
Talk about an emphatic way to pick up a first win as manager - Aitor Karanka had steered Granada to draws with Atletico Madrid and Celta Vigo before the journey to Mallorca, and the new manager bounce was in full effect in that basement battle.
Luis Suarez, Myrto Uzuni, Antonio Puertas, Sergio Escudero all netted alongside a brace from 40-year-old Jorge Molina in a phenomenal goalscoring showing from Granada, who began the day in 18th but are now in control of their fate once again.
By thrashing Mallorca in gameweek 35, Granada have risen out of the dreaded drop zone and are two clear of Javier Aguirre's side with three games left to play, and Karanka is still unbeaten since his arrival in the Granada hotseat.
Next on the agenda for Karanka is ending an eight-game winless home run stretching all the way back to their 2-1 success over Atletico Madrid just before Christmas, but facing Athletic, Real Betis and Espanyol is a far from straightforward end to the season for the former Europa League contenders.
Despite witnessing opposing defender Gabriel Paulista stretchered off with a serious ankle injury and Hugo Guillamon given his marching orders in the dying embers, Athletic Bilbao just could not find a way through the Los Che backline in gameweek 35.
While Marcelino will certainly regard that 0-0 stalemate as two points dropped rather than one point gained, Athletic are not out of the European conversation just yet and could yet break into the top five if results go their way in the final few weeks.
As things stand, Athletic sit just outside the European places in eighth but are just one point adrift of Villarreal - who drew with Sevilla on Sunday afternoon - and taking seven points from their last three games sure has aided Marcelino's bid for continental football at San Mames.
Only one of Athletic's last six away games in all tournaments has ended in victory, and they were held to a 2-2 draw by Granada on their own territory back in November, but the hosts' aspirations of another goal-laden performance are far less realistic with the treatment room now filling up again.
Granada did not come out of their thrashing of Mallorca unscathed by any means, as goalscorers Suarez and Escudero were taken off with thigh and adductor problems respectively, and Njegos Petrovic is now suspended.
Carlos Neva, Ruben Rochina, Raul Torrente and Daniel Raba all remain in the treatment room for the hosts, and Puertas was also forced to come off against Mallorca after trying and failing to continue with an unspecified issue.
Karanka will therefore be forced into some unwanted alterations here, with Molina and Uzuni likely to come into the first XI, and Maxime Gonalons should cover for the suspended Petrovic.
Athletic seemingly came out of their clash with Valencia without picking up any fresh problems, but Yeray Alvarez, Unai Nunez, Ander Capa and Oscar de Marcos have now joined Oihan Sancet in the treatment room.
The quick turnaround should also benefit Unai Vencedor and Alex Berenguer's bid to return to the starting lineup, while Dani Garcia and Inaki Williams are both only one booking away from a one-game ban.
Granada possible starting lineup:
Maximiano; Quini, Sanchez, Diaz, Arias; Gonalons, Milla; Uzuni, Collado, Machis; Molina
Athletic Bilbao possible starting lineup:
Simon; Pexta, Vivian, Martinez, Balenziaga; Berenguer, Vencedor, D. Garcia, Muniain; I. Williams, R. Garcia
We say: Granada 0-2 Athletic Bilbao
Now coming up against a defensively sound Athletic Bilbao side having suffered fresh injury blows with three of their goalscorers at the weekend, Granada's strong start to life under Karanka could come to a grinding halt here.
The hosts have not had the winning formula in front of their own fans of late, and with Marcelino's men in rather strong form themselves, the European outsiders can take advantage of Granada's lengthy injury list to get back on track.
Our analysis of all available data, including recent performances and player stats, suggests the most likely outcome of this match is a Athletic Bilbao win with a probability of 44.18%. A win for Granada has a probability of 29.86% and a draw has a probability of 26%.
The most likely scoreline is Granada 1-1 Athletic Bilbao with a probability of 12.35%. The next most likely scorelines are 0-1 (10.72%), 1-2 (9.01%), 1-0 (8.47%).