Mark Turgeon turned 47 years old last month. He has flecks of gray hair, and he’s a little crinkly around the eyes. But in the ACC coaching ranks, he’s a rookie, one of an unprecedented four coaching in this week’s ACC tournament at Philips Arena.

Turgeon had the dead-giveaway look of a rookie ACC coach on his previous trip to Philips Arena 10 days ago. His right hand was latched to the right side of his face throughout his postgame interview on Feb. 25, after his upstart Terrapins were upset by Georgia Tech, then the last-place team in the ACC.

“I thought we were growing up, I really did,” he said in quiet monotone. “But today showed that we haven’t grown up all the way. We weren’t ready to play.”

Maryland was playing its fifth game without injured point guard Pe’shon Howard, but still had a chance to move to .500 in the ACC and into a tie for fifth place. The Terrapins were picked to finish ninth. After losing three in a row to end the season, they ultimately fell to an eighth seed.

Maybe it was a letdown after rallying to beat Miami four days earlier, but the Terrapins showed tell-tale signs of a young team in the throes of an ACC schedule: inconsistency, struggles on the road (they are 1-7 in ACC road games) and a loss to a last-place but still dangerous team.

“Every game is a huge battle,” said Miami coach Jim Larranaga, who at age 62 is a rookie in the ACC, too. “Every team is very, very well coached, and very, very well prepared. Everybody is very good on their home court, and many of the teams are very, very tough on the road.”

“Well-coached” is a cliché coaches always seem to toss around about each other, playing nice in front of the TV cameras. But if you ask Georgia Tech coach Brian Gregory, who along with N.C. State’s Mark Gottfried completes the ACC rookie foursome, it’s absolutely true.

In a league with Duke’s Mike Krzyzewski, who became college basketball’s all-time winningest coach in November, and Roy Williams, who has won two national titles at North Carolina and has made seven Final Four appearances, including four at Kansas, the standard is high.

Gregory sees it continuing with the new group of coaches, who account for two-thirds of the league ranks now that eight coaches have joined the ACC since Tony Bennett was hired at Virginia in March 2009.

Gregory, who coached in the Big Ten as an assistant at Michigan State and in the Atlantic 10 for eight years as the head coach at Dayton, said it’s been a noticeable change — the level of coaching in the ACC.

“It’s really good,” Gregory said. “They take advantage of any mistake you make.”

Gregory said he had a baseline out-of-bounds defense he used for the past four years at Dayton to much success, forcing turnovers and five-second calls. He said maybe one team per season would foil it and force him to adjust it. This year, while running it at Tech?

“Five, six, seven teams in this league have found a couple cracks in it,” Gregory said.

Gregory said a lack of familiarity with other coaches’ tendencies, and other players for that matter, has forced him to spend more time in scouting and preparation this season than he might ordinarily do later in his tenure.

Turgeon agrees. He’ll spend time this summer watching film, but said there’s no substitute for living through a season.

“Coaches coach a certain way — getting a feel for them, physical teams, finesse teams, running teams,” Turgeon said. “You have really got to go through it to understand it.”

Turgeon said that what he’s seen in person from players came as somewhat of a surprise, too.

“The talent level was a little better than I was expecting,” Turgeon said. “The league is very long and athletic, and [there are] a lot of smart players in this league.”

One thing that’s surprised Gregory is the physical nature of the ACC, as well as having an officiating crew that by and large lets players play, which he appreciates.

“I think the outside perception is that it’s kind of finesse, tea and crumpets,” Gregory said. “It’s definitely more baloney sandwiches, more of a lunch pail than a nice picnic-on-a-blanket type of deal.”

Gregory thinks the influx of new coaches and their philosophies might have something to do with that.

All four of the rookie coaches bring significant experience to the mix. The youngest of the four is Gregory at 45. They’ve all been head coaches in Division I with success in the NCAA tournament to draw on — Gregory at Dayton, Larranaga at George Mason, Gottfried at Alabama and Murray State and Turgeon at Texas A&M and Wichita State.

If they were really truly rookies, they might not have made it this far, to the brink of their first tastes of the ACC tournament.

“It’d be a bloodbath,” Gregory said.

All four coaches have rebuilt in the past and seen it work, so they have confidence in what they’re doing.

Guys like Turgeon needed it. While facing a season-ending injury to his point guard, and with a roster whittled down to seven scholarship players and six walk-ons, Maryland played a schedule that featured both North Carolina and Duke twice — the only team in the ACC who did that in the regular season.

“I can’t imagine,” said Turgeon when asked if this had been his first job, not his fourth. “I’ve been through it, I know what to expect. If you’ve proven yourself before and you believe in what you’re doing, you know it’s going to work. You’ve just got to stay the course, and that’s what we plan on doing here.”