The Hammers suffered a 2-0 defeat to the newly-crowned Bundesliga champions in last week's first leg held in Germany, courtesy of two late goals from substitutes Jonas Hofmann and Victor Boniface.
Goalkeeper Lukasz Fabianski made an impressive nine saves to ensure David Moyes's side remain in the tie following a powderpuff attacking display — registering just one shot on goal and boasting only 27% possession throughout the 90 minutes.
West Ham sorely missed the presence of top scorer Jarrod Bowen, who was ruled out of the first leg and also missed last weekend's 2-0 Premier League defeat at home to Fulham due to a back issue.
The Hammers also had to cope without Alphonse Areola (groin) and Kalvin Phillips (hamstring) due to injury, while Edson Alvarez was absent against Leverkusen through suspension.
Bowen, Areola, Phillips all train ahead of Leverkusen clashWest Ham can welcome back Alvarez on Thursday and three more players could also return as Moyes has confirmed that each of Bowen, Areola and Phillips have taken part in first-team training.
Providing a fitness update on his squad at a press conference on Wednesday, Moyes said: «It was great to see [Bowen] out there, it was the first time we've had him out (since his injury).
»Not sure yet [if he will be involved], we had Kalvin [Phillips] out as well but I'm not sure about him either. Alphonse [Areola] was out as well but I'm not sure about him either. They'll all be pretty late calls tomorrow."
«Most people know exactly what Jarrod's done for us over this season, and other seasons also,» Moyes added.
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