Since spring practice opened at Michigan and Northwestern this week, we’ve been ranking position groups around the Big Ten. For previous entries in the series, click here.

We come now to the end, with special teams. Since it's virtually impossible to predict what kick coverage units will look like several months from now or project how new starters will fare on field goals and such, we're basing these rankings mostly on who's coming back at place-kicker, punter and returner.

Here we go:

Best of the best: Maryland

The Terrapins return the 2014 Lou Groza Award winner in Brad Craddock, who missed only one field goal all of last season. They also bring back an elite return man in Will Likely, who led the Big Ten in kickoff return average and was third on punt return average last year. Punter Nate Renfro is also back, giving Randy Edsall both experience and trust at the key specialist spots.

Next up: Ohio State

It's entirely possible that Cam Johnston is a wizard, as his rugby-style punts somehow both cover a ton of distance yet seem to stop at the right places. He was brilliant in the Sugar Bowl. The Buckeyes also have a boatload of speed they can use in the return game, including Jalin Marshall and Dontre Wilson. Place-kicker Sean Nuernberger is back after a respectable freshman campaign, but it's not like Urban Meyer really wants to kick field goals, anyway.

Sleepers: Nebraska and Minnesota

"Sleeper" isn't really the right word here, but we wanted to give a shout out to both of these special-teams units.

The Huskers have one of the nation's most electrifying punt return men in De'Mornay Pierson-El, who averaged 17.5 yards per attempt and scored three touchdowns last year. Punter Sam Foltz and kicker Drew Brown also return and could improve with experience.

Minnesota has the reigning Big Ten punter of the year in Peter Mortell, plus highly productive returners Jalen Myrick and Craig James. More accuracy from kicker Ryan Santoso (12-of-18 as a freshman) would solidify the Gophers as one of the best special-teams groups around.

Problem for contenders: Penn State and Michigan

Again, it's nearly impossible to predict how new kickers will fare, as you don't really get to see how they will fare in pressure situations until the games begin. Both the Nittany Lions and Wolverines have some big shoes to fill.

Place-kicker Sam Ficken was far and away the best thing about Penn State's otherwise highly shaky special teams in 2014, and now he's graduated. The team doesn't have a scholarship kicker on the roster and may turn to walk-on Joe Julius. Punt and return teams must make major strides as well.

Michigan lost both its place-kicker (Matt Wile) and punter (Will Hagerup) to graduation, and its return game was no better than average last season. New special-teams coach John Baxter will have his work cut out for him this spring in bringing some new names -- like freshman kicker Andrew Davis -- along.