Santander could frustrate Bilbao, but they might not have enough goals in them to win this.
Santander's long home winning sequence is over, but they will make this tough for the visitors.
Bilbao lost on the road on Monday night and another tough away trip awaits.
Bet365 make Santander 4/1 for victory here with Bilbao priced at 8/13
Athletic Bilbao have very mixed form this season. They are always strong at the San Memes Stadium, but tend to trip up and drop points on the road. They faced a long trip back home after a loss against Las Palmas on Monday night which saw Adruiz dismissed in the second half. He saw red for dissent as Bilbao tried to forge a way back into the match.
There's no shame in losing on the Island with Las Palmas unbeaten in seven here, but Bilbao were caught out by a swift counter attack and it's something they will need to ensure doesn't occur here.
Raul Garcia has been in superb form recently, but Ernesto Valverde may be tempted to rest a few players here.
With the home leg to come, Bilbao will be confident of progressing, but they can't afford to give their hosts too much of an advantage.
Santander have been solid at home this season, although their form has dropped off slightly in recent weeks.
Between the end of August and the middle of October, they went on a 7 match winning sequence, but have only picked up 2 points from a possible 9 in their subsequent three encounters.
They've only lost once here and got back to winning ways on the road at the weekend. It leaves them in 2nd place, but with an 8 point deficit to make up on Leonesa.
I don't think this will be straightforward for Bilbao. Take a chance on Santander or Draw on the Double Chance market at 13/10 with Bet365
Athletic Bilbao are usually good for a goal and have netted in all but one of their La Liga away games this season. Back Both Teams to Score at 19/20 with Bet365