It was determined that the former Middlesbrough and Sheffield Wednesday man would not require an operation, but that option came with a risk of re-injury.
And Reach, who had been on target during behind-closed-doors friendlies this summer, was substituted off in the friendly at Burton after pulling up a couple of weekends ago. He will go under the knife and not be available until later in the calendar year.
“Reach suffered one important injury last year," explained head coach Carlos Corberan. "With the injury you have two possibilities, make a surgery or a more conservative treatment without the surgery.
“The difference is about how much the tendon is affected, our medical staff understood the tendon wasn’t damaged enough to proceed with surgery and have treatment of some months.
“Unfortunately in football 50 per cent of injuries that damage the muscle and don’t have surgery you have a risk to have the injury again and unfortunately this is exactly what happened with Reach. As soon as you have the same injury the second time you need to proceed with surgery.