Morelos has not made the best of starts this season and looked lacklustre in Rangers’ 2-1 win over St. Johnstone over the weekend.
The Colombian recently admitted he remains keen to take the next step in his career away from Ibrox.
There are calls for Gerrard to drop Morelos to the bench, but Ferguson conceded that he understands that the forward probably wants to play in the Premier League.
But insisted that he needs to forget that at the moment as the transfer window is closed and no club have matched Rangers’ asking price.
However, he stressed that Morelos needs to be in the team as Rangers are better with him and when in form, he is still the best striker in Scotland.
The Rangers legend said on the Go Radio Football Show: “He clearly wants to play in one of the best leagues – the English Premier League and I get that.
“But he needs to get that out of his mind now as nothing is happening.
“Rangers have been open and honest – there is a price on his head, it has not been matched and he doesn’t go.
“For me, he looked a bit off, but Rangers are a better team [with him], I have maintained that even when he was getting sent off and his disciplinary record wasn’t great.
“Take the edge off him, he is not the same player and I like him, I have always liked him and when he is on his game he is the best striker in Scotland.
“And the manager will always play him.”
Morelos has scored just once in the Scottish Premiership this season and has netted three in eight appearances in all competitions.