The 21 year-old, who has signed on loan at Posh until the end of the season, is in the latter stages of a recovery from a hamstring injury.
He is ineligible to play against his parent club West Bromwich Albion on January 22 so his debut won’t take place until the rearranged game at Birmingham City on Tuesday, January 25, at the earliest.
Posh boss Darren Ferguson is delighted to have Morton on board though.
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“He gives us something I believe we need,” Ferguson said. “He is full of energy, he wants to play on the shoulder and he want to run in behind.
“He’s quick enough. He makes intelligent runs. He likes to penetrate using good movement. We need someone who is able to break the lines and take advantage of the creative players we have in a midfield diamond.
“Given the market and how we are able to compete, he is a very good signing for us. He’s probably better with someone alongside him which is something for us to look at.
“West Brom have been good with us. They’ve let Callum come earlier than we expected, but unfortunately he won’t be ready for Saturday and he can’t play the following week so we are looking at the Birmingham game for his first appearance.
“With Jack Marriott not far away, Ricky-Jade Jones back and a very highly motivated Jonson Clarke-Harris we now have good options up front.”
Posh will again be without attacking midfielder Joel Randall on Saturday. Posh are determined to not to rush back a player who has been bedevilled by injuries since signing for Posh in a million-pound deal in the summer. Randall currently has a hamstring issue.
“Joel should be back training on Monday,” Ferguson added. “We are not going to rush him as if he breaks down again it could be an entire season written off for a player we spent a lot of money on. Joel is a very good player. I’d rather he played the final 18-19 games of the season rather than the next two when he might break down.”
Ferguson has a decision to make between regular number one Dai Cornell and new goalkeeper signing Steven Benda for the Coventry game.
Benda joined Posh on loan from Swansea earlier in the week after taking a big paycut to make the move.
Ferguson said: “I have a decision to make there. Steven obviously wants to play and he’s made sacrifices to come here which shows his commitment.”