Les Olympiens' upswing after Jean-Louis Gasset's arrival is well and truly over, with the Ligue 1 side unable to string results together in recent weeks, and they host an in-form side that have lost just once in nine games.
Match preview
Gasset's arrival at Marseille caused a difference in performances and results, but the Ligue 1 side have been brought back down to earth with the recent five losses in all competitions.
While Gennaro Gattuso's departure and Gasset's appointment saw Marseille average 3.6 goals a game in a five-match winning sequence, the French side's mean has dipped to 0.6 with Les Olympiens failing to score in two of the recent five losses against Rennes (2-0) and PSG (2-0) and notching no more than a solitary goal in defeats to Villarreal (3-1), Lille (3-1) and last week's 2-1 loss to Benfica.
Losses to Villarreal and Benfica could be considered differently because the Olympians had defeated the Spanish side 4-0 in the first leg and could still turn the tie around against Benfica, having scored in Lisbon through Pierre-Emerick Aubameyang.
The competition's top scorer (34) overtook Radamel Falcao's 30 strikes earlier this year and could add to his tally as he nears Henrik Larsson's 40 goals in Europe's secondary club competition (considering qualifying games).
Marseille returning to winning ways is the higher ambition, as they seek to take advantage of having last weekend off in Ligue 1 to overturn a deficit on the continent for the first time since the 2017-18 campaign.
As for Benfica, their European hoodoo goes even further to the 2013-14 campaign — the last time they made it to the last four of any continental competition.
The Eagles were defeated by Juventus in the semi-final on that occasion, and Roger Schmidt is keen to end that decade-long wait this year.
The away side head into the encounter in fine fettle, having suffered just the one reverse in the last nine to domestic rivals Sporting at the start of April, winning six and drawing two of their other fixtures since suffering back-to-back losses against Sporting in the cup (2-1) and Porto in the topflight (5-0).
Schmidt's men could have gone into Thursday with a more positive feeling had they prevented Aubameyang from halving Benfica's lead and giving Marseille a lifeline heading into the reverse fixture in France.
Both sides have suffered setbacks on the continent in recent years, but they head into this week's quarter-final second leg knowing they have the opportunity to end their respective dispiriting streaks.
Benfica have stayed undefeated since dropping into Europe's secondary club competition this year, notably keeping clean sheets at Toulouse (0-0) and Rangers (1-0), and the Portuguese side hope their ability to secure needed results on their travels so far bodes well for their visit to the Velodrome.
Marseille Europa League form:
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Marseille form (all competitions):
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Benfica Europa League form:
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Benfica form (all competitions):
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Team News
Gasset has multiple injuries plaguing his side, with Marseille possibly without Ismaila Sarr, Jonathan Clauss (both hamstring), Bamo Meite, Quentin Merlin (both ankle), Jean Onana (muscle), Valentin Rongier (knee) and Bilal Nadir for Thursday.
With Sarr (two goals) out of the picture, the Olympians hope Jordan Veretout (three) supplies aid for Aubameyang (10), with the experienced striker hitherto dominating this year's competition.
Juan Bernat is Benfica's only injury doubt for Thursday's visit to Marseille, pointing to the Eagles' advantage of added options off the bench.
Angel Di Maria's five goals plus assists dominate the Portuguese side's return, with Rafa Silva (two) trailing the 2022 World Cup winner, making the experienced man the away side's go-to for navigating a tricky visit to the Velodrome.
Marseille possible starting lineup:
Lopez; Gigot, Balerdi, Mbemba; Harit, Ounahi, Kondogbia, Veretout, Ndiaye; Aubameyang, Moumbagna
Benfica possible starting lineup:
Trubin; Bah, Silva, Otamendi, Aursnes; Florentino, Neves; Di Maria, Rafa, Neres; Tengstedt