Sunderland's need for attacking reinforcements has been underlined by a hamstring injury to Jerome Sinclair.
The Watford loanee came off after a promising cameo against Charlton Athletic on Saturday, visibly frustrated as he left the field.
The 21-year-old is set to be out for at least a month, leaving Jack Ross short on attacking options.
New signing Charlie Wyke is still recovering from an injury picked up in pre-season.
After the 2-1 win at the Stadium of Light, Ross confirmed that Sinclair's situation could affect what he needs to do in the closing stages of the transfer window.
He said: "[There will be] possibly a couple more outs, then we may have to assess the injury situation. “Assess Jerome’s hamstring injury, the seriousness of that. That will leave us light in forward areas because we already were.
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“Even today when you look at the bench it was all academy players, even though Jerome is young and Bryan obviously has experience.
“I would expect there will be a little more movement but I wanted this [game] out the way first and then maybe have a look.”
Ross is also set to be without full-back Donald Love for a month.
Love was replaced by Bryan Oviedo in the opening stages of the game on Saturday and left with his ankle in a protective boot.