Winchester was withdrawn in the early stages of Sunderland’s 5-1 win over Cambridge United last Saturday with a groin problem, and a scan has suggested that he is facing weeks on the sidelines.
Should Sunderland manage to secure their place in the top-six at Morecambe on Saturday, they would face a quick turnaround to the play-off semi finals which are due to take place on May 5/6th and 8/9th.
The final is then scheduled to take place on May 21st at Wembley.
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"It’s not particularly good news on that one, it’s certainly looking like weeks rather than days,” Neil said of Winchester.
There is better news on Dennis Cirkin, who is unlikely to be involved in Saturday’s crucial game but is nearing a return to full training.
“Dennis is not far away now, which is good news,” Neil said this morning.
“He’s pain-free in his calf now which is good, so it’s just a case of stepping up his preparations.”
Losing Winchester and Cirkin leaves Neil with a dilemma in terms of his defensive set-up, having had to move Lynden Gooch across to the left flank against Rotherham.
“It’s been difficult since the get-go to be honest, it’s not been easy,” Neil said.
“What can sometimes happen is when a player comes out you lose an ingredient, but you add another one. It’s just trying to make sure that you get the balance right for what’s coming in the next game.
“That can be a challenge, when you lose Dennis and Carl is that natural pace in your backline to get out and defend the sides 1-v-1.
“But when they are not there, there are other guys who can bring different strengths as well.
“Naturally, there are certain areas of the pitch where we need to make sure that we’re covered and that we’ve got guys who can fulfil the roles that we need,” he added.
“Goochy for example, I didn’t really want to move him from wide right because we would all agree that against Cambridge was excellent, but when you have those gaps it becomes a needs-must scenario.
“For that match I felt it was necessary.”