Semi-final spots on the line

With three of the first legs finishing 2-1 to the home side, there is all to play for when the UEFA Europa League quarter-finals conclude on Thursday. UEFA.com examines the four ties, which all kick off at 21.05CET.

Valencia CF 1-2 AZ Alkmaar (first leg; second leg)
The Spanish side had never lost to Dutch opposition before Thursday's first leg, but AZ are a tough nut to crack and Maarten Martens' goal 11 minutes from time has given them a slight edge. They have also won two of their previous four games in Spain, but Valencia have their own reasons to be confident after scoring four goals in each of their last two home contests against Eredivisie sides. AZ are flying high at home and in Europe – a positive result at Mestalla would be another feather in the cap for coach Gertjan Verbeek.

Athletic Club 4-2 FC Schalke 04 (first leg; second leg)
Athletic continue to entertain and score freely in some of Europe's most daunting arenas. After hitting three goals away to Manchester United FC in the round of 16, Marcelo Bielsa's men were at it again at the Arena AufSchalke – coming from behind to take a big advantage into the home return. Schalke won 3-0 at Maccabi Haifa FC in the group stage and need a similar result to progress; Athletic have lost just once by that scoreline in Europe, but it was to Bundesliga opponents in SV Werder Bremen in 2009.

FC Metalist Kharkiv 1-2 Sporting Clube de Portugal (first leg; second leg)
The competition's top scorers looked like they would be facing a steep climb to make the last four when trailing by two goals going into the final throes of the first leg. However, an added-time penalty from captain Cleiton Xavier has thrown an entirely new light on the tie. Even so, Sporting's win was their fifth straight victory against Ukrainian opposition and Metalist are in unprecedented territory – the round of 16 is the furthest they have been in Europe before this season.

Hannover 96 1-2 Club Atlético de Madrid (first leg; second leg)
Hannover are enjoying a dream season in the UEFA Europa League; it is only their second European campaign and their first ended after one tie – against a fellow Bundesliga team. This time round, they are very much in contention for a place in the semi-finals after scoring a crucial away goal at the 2010 winners. To further display the disparity in continental exploits between the clubs, Falcao's opener in that game was Atlético's 400th in UEFA competition – but they may need to call on all of that experience to hold off Mirko Slomka's lively outfit.

Semi-finals (19 April & 26 April)
1: Atlético/Hannover v AZ/Valencia
2: Sporting/Metalist v Schalke/Athletic

Final (9 May, National Arena, Bucharest, 20.45CET)
Winner semi-final 1 v Winner semi-final 2