But that doesn't mean there's no vacancy sign attached to the Mike position on Saturdays next fall.
"Jarrett Grace is exceeding expectations of a first-year player," Diaco said of the redshirt-freshman from Colerain, Ohio. "He's mature, tough, smart, has enough tangible skills to get the jobs done on the inside, and he's off the charts with all the intangible traits. He'll be a hard guy to keep out of the games."
For the past two-plus seasons, it's been difficult to take Te'o off the field, both for Diaco and former defensive coordinators in need of the All-America candidate's toughness, athleticism, and instincts in the trenches. But neither Te'o nor the Irish defense has been close to infallible, and Diaco's job is to find the best 20-plus defenders to fit into each unique game day situation.
"There are a lot of jobs to do," Diaco continued of Grace's potential for playing time. "Manti has shown that there are times that he doesn't have to be in there, or can't be in there. Those opportunities will (present a time) when Grace will go in.
"He's a hard guy to keep off the field, (but) it doesn't have to be at Mike. There are four running teams (special teams coverage and return units); he could be on all four. There are other sub package roles he could do (from scrimmage). If he keeps developing he'll be hard to keep off the field."
Grace was withheld from action last season but routinely lauded by the defensive staff and Kelly when the coaches were pressed for information on young players not seen by the masses. His ascent isn't meteoric; Diaco and Kelly knew they had something special before he stepped on campus.
"We always felt that in the recruiting process we had a special person there, (one) who has some off the chart intangible ability that most don't have," Diaco said of Grace who forged his way onto the two-deep (but did not play) when the Irish faced option foes Air Force and Navy last year.
"When you saw him with the (second string) we were playing option. He has a unique background for preparation with option in that he saw it his whole life. The team he played for (Colerain, HS) ran option. If we had to go to him he'd have been the next best available to play that particular game."
Coincidentally, Notre Dame's opening opponent is well-versed in the triple-option attack…it appears Grace's services won't be saved much longer.
Seeing is BelievingGrace's classmate and fellow 2011 Scout Team member Ben Councell also received a positive review from his position coach and coordinator.
"Ben Councell is doing a great job. Bigger, faster, stronger (than last year)…he's changing direction well," said Diaco of the Dog/Drop linebacker and special teams competitor. "He's smart, tough, and he's a big bodied guy at 6'4½" or 6'5"
"He is exactly what we're looking for in profile out there."
Another former redshirt, 2010 recruit Kendall Moore, made his debut on the Irish special teams last fall as a regular on the team's kickoff return and coverage unit. Moore continues to push for playing time among the inside linebackers but it appears uneven daily performance remains his biggest detriment to scrimmage snaps.
"Kendall is doing a nice job. He has to work on his consistency and his preparation," Diaco offered, adding, "We believe what we see. If the player is consistent and accountable, and doing the right things, then we have an expectation that when it comes to a critical down, that he's going to do the right thing and be accountable.
"And if not, then we believe that too."