Ohio State lost a lot of talent to the NFL, and for Ryan Day to make his Buckeyes a College Football Playoff contender in 2019, he'll need several position groups to have a big offseason.
The wide receiver group lost three of its top four contributors, yet remains deep and talented with returnees like K.J. Hill, Austin Mack, Binjimen Victor and emerging sophomore Chris Olave.
The running back room took a hit as well with the early deflection of Mike Weber and transfer of Brian Snead, but it's in good hands with J.K. Dobbins primed to step into a primary role.
With talent at key positions but question marks elsewhere, these are the four position groups that need to grow up fast before the season kicks off.
Offensive Line
The big group up front took the biggest hit with the loss/departures of four starters. Thayer Munford is back as the foundation of the unit at left tackle, but the rest of the line will be completely overhauled by opening week.
Branded Bowen (projected left guard), Wyatt Davis (projected right guard) and Joshua Alabi (projected right tackle) bring some playing experience to the field, and former 5-star Josh Myers looks like a great option at center.
The big concern comes with the two deep. Ohio State has just 11 scholarship offensive linemen on the roster and will look to add more on signing day next month.
Look for a lot of attention to be paid to the Buckeyes' offensive line during spring and fall camps.
Quarterback
It's rare for a school to lose its starting and backup quarterbacks when both had multiple years of eligibility remaining, but that's the situation Ohio State finds itself in after the early deflection of Dwayne Haskins and Tate Martell.
Haskins rewrote Ohio State (and the Big Ten's) passing records in his lone season as a starter. Martell looked next in line, but with Meyer's retirement and a departure of the playing style that best fits his skill set, the Las Vegas product was already climbing uphill.
Then Day and the Buckeyes landed Justin Fields, the former 5-star standout and Georgia Bulldog who entered the transfer portal earlier this month. Fields has a good chance of earning a waiver to gain immediate eligibility at Ohio State, and if he does, he'll compete with Matthew Baldwin for the starting job next season.
Linebacker
Unlike the first two position groups, the linebackers return all of its starters from a season ago in Tuf Borland, Malik Harrison and Pete Werner. The reason the unit is on this list is because they greatly underperformed in 2018, and Ohio State needs drastic improvements from the middle of its defense to remain a playoff contender next season and beyond.
A coaching overhaul should help. Day brought in former Michigan defensive coordinator and defensive line coach Greg Mattison to co-coordinate the defense with Jeff Hafley, who was hired away from the San Francisco 49ers. Day also replaced former linebackers coach Bill Davis with Al Washington, who coached the same group at Michigan a season ago.
Secondary
Much like the linebacker unit, Ohio State's secondary returns a lot of experience that gave up too many big plays in 2018.
Multi-year starter safety Jordan Fuller will anchor the group, and he'll be flanked by Brendon White, who broke out down the stretch and provided the back end of Ohio State's defense some much needed playmaking ability.
Cornerback Kendall Sheffield is the only departing starter, but the return of Damon Arnette boosts a group that includes Jeffrey Okudah and Shaun Wade.
Haffley will take over coaching the back end along with co-secondary coach Matt Barnes, and they'll have a lot of work to as they overhaul a secondary that ranked 86th nationally in passing yards allowed.
