The 23-year-old powerhouse was withdrawn by manager Thomas Christiansen in the 38th minute of Leeds' 3-1 win over QPR on Saturday afternoon, which saw Kemar Roofe score an impressive hat-trick at Loftus Road.
Ekuban, who was replaced by outcast Pawel Cibicki, had previously been sidelined for more than two months of Leeds' 2017-18 campaign with a broken foot and now there are fears that he has worsened the injury.
The Italian striker, who joined the Whites from Serie A outfit Chievo in the summer, posted a picture on his Instagram story that showed him lying down with a protective boot on his right foot.
It remains to be seen if the former FK Partizani ace has suffered a similar injury to the previous problem that has kept him sidelined for much of the season. If that is the case, Christiansen will be struggling for options up top.
Hamburg loanee Pierre-Michel Lasogga's form has been poor since moving to Elland Road and he missed Saturday's clash through injury, while Cibicki's Saturday appearance was his first in the Championship. Jay-Roy Grot is also yet to impress.
Christiansen will be hopeful that Ekuban can return sooner than his recent spell on the sidelines, but judging by his post, it certainly does not look good for Leeds or the young striker.