Sporting have been revitalised since sacking Domingos Paciencia and replacing him with Ricardo Sa Pinto in Feburary. The new manager has led the side to 6 wins in 8 league games and knocked Manchester City and Metalist Kharkiv out of the competition.
Elias is still ineligible in the Europa League and could be replaced in midfield by Daniel Carrico or Andre Martins.
Anderson Polga, Ricky van Wolfswinkel, Marat Izmailov, Andre Carrillo and Fabian Rinaudo are all one yellow card away from a European suspension, though no Sporting players are out of this game for disciplinary reasons.
A huge blow for Athletic Bilbao is the absence through suspension of key man Javi Martinez. He will be back for the second leg, and Marcelo Bielsa will be keen that none of Muniain, Herrera, de Marcos or San Jose pick up a yellow card which would keep them out of the return leg.
Gurpegi, Castillo, Ocio and Perez are all out through injury, but apart from Martinez, the Athletic team should stay largely unchanged from the team that drew against Schalke in the last round.
Fernando Llorente has been struggling with a niggling injury, having completed the full 90 minutes only twice in Athletic's last 13 matches. He will, however, lead the line once again, providing much of Athletic's attacking threat.
Sporting have a formidable home record this season, having lost only once on home soil, and that loss came way back in August. Since that loss they have won 19 and drawn 2 of their 21 home matches in all competitions, and have conceded in only 2 of their last 16 home games, including clean sheets against Benfica, Porto, Braga and Manchester City. Athletic are clearly up against it.
Marcelo Bielsa's side will have to improve if they are to get a result here. They have won only 3 of their last 9 matches, and only 2 of their last 9 away games. It is very interesting, though, that those 2 away wins for the Basque side have been their 2 most recent away games in the Euopa League - equally impressive victories over Manchester United and Schalke. Both times Athletic conceded twice but managed to outscore their opponents. Given that they have already reached the Copa del Rey final, Bilbao are guaranteed to be playing in the Europa League again next season, so they have let up in the league somewhat - their priority clearly being to go as far as possible in the continental competition.
Bielsa will certainly have done his research on his side's Portuguese opponents, and they have spring a huge surprise in their latest Europa League games. They have a potent attack and even though Sporting do not concede many at home, Bilbao will probably have enough to break through a stubborn defence. Given Sporting's impeccable home record and Athletic's ability to do the unexpected, this could end in a score draw, with Athletic's away goals giving them the advantage going into the second leg.
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