The German has not played since the first three Premier League games of the season.
Fullkrug has been absent with an Achilles tendon injury that took longer than expected to clear up.
On Monday, boss Julen Lopetegui stated about the forward: “He is improving.
“He’s definitely very close. Tomorrow (game against Leicester City) is going to be difficult to (play). But hopefully the next matches he’s going to be available.
“For sure, (he will not be) in his best fitness, because he has to recover all this fitness — three months is a lot of time without matches. But fortunately he’s on the end of his recovery time.
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