Mark Turgeon’s No. 1 rule heading into his first season at Maryland? “You can’t get hurt!” he says, underscoring the rule’s importance, at the ACC’s media day in Charlotte. “Especially with only eight [scholarship] players — they can’t get hurt.” (Chuck Burton/AP)

While it’s only six practices into Mark Turgeon’s tenure, Maryland’s first-year coach already has introduced his players to the base defense he intends to run, several offensive plays and one non-negotiable rule.

“You can’t get hurt!” Turgeon said, underscoring the rule’s importance. “Especially with only eight [scholarship] players — they can’t get hurt.”

Maryland’s thin roster of returning players was the dominant Terrapins story line Wednesday as ACC basketball coaches gathered in Charlotte for the annual preseason media day.

With last year’s leading scorer and rebounder, Jordan Williams, bailing early for the NBA, and the eligibility of Ukrainian center Alex Len in limbo, Maryland was picked to finish ninth in the 12-team league — its lowest projection since the media poll has been conducted. Only Georgia Tech, Wake Forest and Boston College were picked lower.

“Ever since I’ve been at Maryland, we were always the underdog,” senior guard Sean Mosley said before the vote was taken, anticipating low expectations for the short-handed Terps. “At the University of Maryland, we’ve always had to fight for everything we earn.”

But the thin roster is affecting more than mere perception. It’s affecting the way Turgeon is structuring practice, stressing conditioning on one hand but not working his squad as long as he’d like for fear of wearing them out before the season begins.

“I’m making sure they’re fresh,” Turgeon said. “It’s a long season, and we’ve got five months ahead of us. I would practice for four hours if I could, but I wouldn’t have any players in about four weeks.”

While Turgeon has filled out the roster with six walk-ons, the Terps’ practices aren’t as effective unless all eight scholarship players are on the floor the entire time. At the moment, those eight are a precious resource Turgeon can’t afford to burn out, particularly with a two games each against North Carolina (which received 57 of 59 first-place votes) and Duke in store.

Turgeon, who led Texas A&M to four consecutive NCAA tournament appearances, is one of four first-year ACC coaches, along with N.C. State’s Mark Gottfried, Georgia Tech’s Brian Gregory and Miami’s Jim Larranaga, who led George Mason to the NCAA Final Four in 2006. In all, there are eight ACC coaches this season with three or fewer years’ experience in the league.

ACC Commissioner John Swofford characterized it as a period of unprecedented change in men’s basketball. And league will be transformed anew in 2014, when Syracuse and Pittsburgh join its ranks.

Swofford said he expected men’s basketball to go to an 18-game conference schedule at that point. It may also split the sport into two divisions. As for the ACC tournament, Swofford said there was strong sentiment for including all 14 teams, which would add a fifth day to the event.

Meanwhile, the task facing Turgeon is formidable, inheriting a 19-14, 7-9 ACC squad that failed to reach the postseason and lost four of its top five scorers,

Five months into the job, Turgeon said that taking over at Maryland was nowhere near the challenge he inherited at Jacksonville State, a team that ranked 308th among 309 Division I schools, yet it wasn’t as enviable as the situation he stepped into at Texas A&M.

“It’s not broke,” Turgeon said of Maryland basketball. “We have good players, but we only have eight of them. We have good kids. And they’ve been well coached.”

In Turgeon’s view, Mosley is chief among them, having emerged as the team’s leader — his voice on the court, in the weight room and the locker room.

At the moment, Turgeon said, Mosley is the only player who would surely make the starting lineup. The rest is in flux, though Turgeon conceded that sophomore Terrell Stoglin has a great chance.

“He can do something you can’t teach: Put the ball in the basket,” Turgeon said.

The coach was bullish on freshman guard Nick Faust, who received one vote Wednesday for ACC Rookie of the Year. He said Ashton Pankey has proved a tough defender, center Berend Weijs has made great strides and boasts a welcome shooting touch and James Padgett has worked unbelievably hard.

Len, the 7-1 center from Ukraine, hasn’t been allowed to practice with the team since Saturday because the NCAA-mandated 45-day window allowing him to participate while his eligibility is being established has expired. Len is able to watch practice, however, and work out on his own.