Double blow for Posh
By Paul Higham
Last Updated: 01/01/70 1:00am
Tyler has been out for some time with a broken hand but was battling back in training and was hoping to figure in Saturday's derby with Northampton Town.
However, despite doing well in training, scans have shown that he is not fully healed and Posh boss Barry Fry will not risk his number one.
"It is another massive blow to Mark and the club," Fry told the club's website.
"In the last two weeks Mark has been superb in training, diving at people's feet, taking crosses and doing everything that he can and both Mark and myself thought it was a formality that he would be given the go-ahead to play straight away.
"However, the X-ray has shown that the bone is only 95 percent healed and until it is 100 percent he won't be risked."
Striker Green will be out of action for around six weeks after tearing his knee cartilage.
Green came on as a substitute in Saturday's defeat against Port Vale when a block tackle resulted in medial ligament and cartilage damage.
The news will be a blow to Fry who is desperately trying to lift his side away from the drop zone in Division Two.