The Scotland Under-21 international was stretchered off in the 1-0 defeat to Belgium last week and was ruled out for at least 12 weeks.
But the new Jambos boss is relieved that Ridgers' damaged posterior cruciate ligament will not force the youngster to go under the knife, meaning his recovery period will be an estimated three months when it might have been considerably longer.
McGlynn, who brought in former St Johnstone keeper Peter Enckelman as back-up on Friday, told the official Hearts website: "It's a bonus for the lad that he doesn't require any surgery.
"It's a bad enough injury without the need for an operation.
"So that's good news for everyone.
"Hopefully his recovery goes well and to the timescale set by the experts."