Charlton tried to sign Newcastle striker Adam Armstrong earlier this month.
But the former England Under-20 international joined promotion rivals Blackburn.
Addicks boss Karl Robinson is struggling to bring in players because of the ongoing takeover talks with owner Roland Duchatelet.
MORE: Player ratings from Charlton’s Checkatrade Trophy defeat to Oxford United
The Liverpudlian said: “It’s hard because we’re trying to bring in players. Adam Armstrong’s gone to Blackburn.
“[Kieffer] Moore has gone to Barnsley. There are a number of strikers who are getting knocked off the list.
“We need a striker and we need to score more. He [Josh Magennis] needs a break, we can’t rely on one striker.”
Armstrong has been prolific with Coventry in League One in the past.
And Charlton are in desperate need of a striker with Josh Magennis the only senior option.
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