UEFA Conference League quarter-final second leg highlights: Strasbourg, Crystal Palace, Rayo Vallecano and Shakhtar Donetsk go through

Crystal Palace and Shakhtar Donetsk avoided too much drama to make it to the UEFA Conference League semi-finals, while Strasbourg pulled off a sensational comeback and Rayo Vallecano rallied to come back from the brink in Athens.

We round up the second-leg action.

Strasbourg 4-0 Mainz (agg: 4-2)

Two goals in each half helped Strasbourg stage a stunning comeback to reach their first-ever European semi-final. Trailing 2-0 from the first leg, Sebastian Nanasi's close-range finish and Abdoul Ouattara's powerful header got the hosts level on aggregate before the interval. Emmanuel Emegha had a penalty saved, but shortly afterwards Julio Enciso tapped into an empty net to give the French side the lead in the tie for the first time. Enciso then provided the delivery for Emegha to nod in Strasbourg's clinching fourth on an historic night for the Ligue 1 club.

AEK Athens 3-1 Rayo Vallecano (agg: 3-4)

AEK fell agonisingly short of a major comeback as Isi Palazón's goal sent Rayo into a maiden UEFA semi-final. The hosts had 16 attempts on goal in the first half as they looked to reduce a 3-0 first-leg deficit, a Zini finish and Răzvan Marin's penalty bringing them within one goal of parity. The former struck again after the restart to level the tie, but Rayo's captain broke through the middle on the hour to restore the Madrid side's aggregate advantage and some sturdy defending in the closing stages guided Íñigo Pérez's side through in only their second European campaign.

Fiorentina 2-1 Crystal Palace (agg: 2-4)

Palace's three-goal lead from the first leg ultimately proved too big for the Viola to overturn. Buoyed by a thumping Ismaïla Sarr header in the 17th minute, the visitors seemed on course for a comfortable night in Florence until the home side struck either side of half-time. Albert Gudmundsson made no mistake from the spot, while substitute Cher Ndour's long-range strike cut the home deficit to two. Palace held on despite a handful of half-chances for Fiorentina and two saves from Dean Henderson, setting up a semi-final showdown with Shakhtar.

AZ Alkmaar 2-2 Shakhtar (agg: 2-5)

Leeroy Echteld had a complete change of personnel from his side's Sunday Eredivisie starting line-up, but his youthful AZ line-up did not get the early goal they were hoping for and Shakhtar extended their aggregate advantage with an incisive thrust forward just before the hour, Kauã Elias slipping the ball through for Alisson Santana to finish. Substitute Isak Jensen replied with a well-struck free-kick, and Matěj Šín volleyed AZ in front on the night. However, Luca Meirelles' neat finish from another break snuffed out any lingering comeback hope.