Welch, a sophomore, has been cleared to practice this week and should be ready to go against Michigan State this weekend, when he will likely split No. 2 duties with Koyack.
Head coach Brian Kelly liked what he saw from Koyack in his debut Saturday.
"You know, he's not afraid to stick his nose in there, and it's interesting, you know, in terms of assignment, he was assignment correct," Kelly said. "We had some other guys that needed to be attentive to their assignments.
"All in all, he did a nice job. He's a kid that's not rattled. I really love his demeanor. First time we put him on the field he didn't have that look that sometimes you're concerned about. I think Ben is going to be fine for us."
Golic has been cleared to practice as well after the junior broke his arm during a preseason practice.
Still, the injury to Ragone is troubling, as the fifth-year senior will have to sit out his final college season after suffering his third major knee injury in the past six years.
Ragone missed the 2008 season after suffering a torn ACL in preseason practice, two years after missing his senior season of high school at Camden Catholic (Cherry Hill, N.J.) because of a knee injury.
"I'm pretty disappointed for him," Kelly said. "He's been a warrior for us in a sense. He's battled through a lot of injuries. He loves to play the game. He loves competition, and we're really going to miss him. He'll still be around our football team. He's going to help mentor some of our younger players, and that brings us to the other tight ends."
Notre Dame could ask the NCAA to grant Ragone a sixth year of eligibility since he would have missed nearly two full seasons due to an injury or circumstance beyond his control.
For now, the Fighting Irish have to be happy with the production they've gotten out of the junior Eifert, whose 10 catches for 144 yards are both good for second on the team.