NBA history is littered with a college coaches who have tried to leap to the NBA’s longer games and vastly longer season and failed.

Timberwolves President of Basketball Operations Flip Saunders vows to look in “all places” for the correct candidate who has both the “clout” and head coaching experience to replace retired Rick Adelman. That likely includes looking at established college coaches — Michigan State’s Tom Izzo, Florida’s Billy Donovan and still possibly Iowa State’s Fred Hoiberg among them.

Here’s a look at what kind of leap a college coach must make, just nine months after Boston tried again by plucking wunderkind Brad Stevens away from the collegiate game:

The Games, Part I

They’re longer.

Eight minutes longer, from college basketball’s two 20-minute halves to the NBA’s four 12-minute quarters.

“It’s much different, it’s 120 possessions versus 70,” the Celtics’ Stevens said last season. “The game is just so much longer, which is twofold: 1. If you get a good thing going, you’ve got to keep that good thing going. No. 2: You might be out of it in a college game with three minutes to go down 10, here you can get right back in it.”

It’s not just the game’s length, either: The NBA has a shorter 24-second shot clock compared to the college game’s 35-second clock. The NBA game also has more and longer timeouts.

“The longer timeouts, the number of timeouts, the number of possessions, the shorter clock … all those things factor into the nuances of the NBA,” said Toronto coach Dwane Casey, a college assistant at Kentucky in the 1980s. “In college, you have the long clock and your continuity offense down pat. In the NBA, you might have 14 seconds on the clock, you might have eight seconds on the clock. There are so many things you have to be prepared for in a shorter amount of time.”

Southern Methodist coach Larry Brown — the only man to win both an NBA and NCAA title — might be exaggerating to make a point but by his calculation a college coach makes a handful of decisions during a game and an NBA coach makes 30. Then, he says, multiply that by 100 games.

The Games, Part II

There are more of them.

So many more.

Donovan coached 39 games at Florida last season, including five NCAA tournament games as the Gators made the Final Four. Izzo coached 38 while leading Michigan State at the Elite Eight. If you count a typical seven- or eight-game preseason schedule, an NBA coach works that many by New Year’s Day.

Donovan’s team won 30 consecutive games last season, from early December after it lost at Connecticut until April’s second week when the Gators lost again to the Huskies, this time in a Final Four semifinal.

That’s more than four months without a loss, if you’re keeping score at home.

Florida lost three games all season.

“You can lose four, five games in eight days in our league,” Saunders said. “In our league, the big thing is how you respond when you lose, not when you win.”

It’s enough to make a college coach’s head spin.

“The coaches who do come here from college were very successful there, and they’re not used to playing and losing that many games,” recently retired Wolves coach Rick Adelman said last season. “You have to learn to adjust.”

It’s good to be King

You’ve probably heard the term “power coach,” a phrase seldom uttered in the NBA unless mention is made of San Antonio’s Gregg Popovich or perhaps the Los Angeles Clippers’ Doc Rivers.

It’s almost mutually exclusive to college basketball’s most successful coaches, men who rule teenagers and sometimes their universities with impunity because of their lavish salary and tenure.

Both of those qualities — at least comparatively in an NBA where the best-paid players make five times or more than nearly all coaches — are rare in the pro league where millionaire players rule.

“It’s a player’s league,” Adelman said. “You better figure that out.”

Head coaches who have been promoted from an NBA assistant’s job seemingly have more success than a coach directly from college.

“It’s apples and oranges, a totally different game in so many ways,” said Toronto assistant coach Bill Bayno, an assistant to Calipari at Massachusetts and a former UNLV head coach. “In college, you’re worried about academics, recruiting, player management. Here it’s all basketball. In college, you have to keep it simpler. Here you can get so much more complex if you have a veteran team. In college, you have to be a dictator because you have 18-, 19-year-old kids, a lot of them come from broken homes that don’t have dads.

“Here you can’t be a dictator. You’re more of a manager. I always remember what Chuck Daly [the former Detroit Pistons coach who died in 2009] said about the NBA: You have to get past mad. In college, you’ve got to get mad. That’s a huge adjustment. It’s just different. You’re not going to figure it out in two or three years, especially if your team is rebuilding.”

Practice time disappears

College teams often play twice a week and their coaches teach the rest of the week. NBA teams can play five times in a week, and between travel and games, practice time is rare.

That’s a difficult transition for many college coaches.

“The NBA is a different coaching animal completely,” Louisville coach Rick Pitino told ESPN Radio’s “Mike and Mike” last week. “When you go from college to the NBA, it’s almost a foreign sport. You’re managing people who play over 100 games and are really not into practicing as much as college kids are, because college kids are looking to practice as much as they can to try and make the NBA. At the pro level, they’re trying to stay away from injuries and protect their bodies.

“Practice in the pros becomes a walkthrough. That’s what the college coaches don’t realize, how much of a different game it is. The pros are almost like being a CEO: You’re managing people to get the most out of them emotionally, physically, strategically, wherein college you’re constantly trying to improve the skills on the athletes on a daily basis.”

Pitino said the NBA landscape changed in 10 years’ time from when he accepted his first NBA job with a Knicks team in 1987 that had Patrick Ewing, Charles Oakley and Mark Jackson until he returned to coach the Celtics a decade later.

“The athlete has changed tremendously,” he said. “I was coaching Ewing, Oakley, Jackson. They were four-year college players who were emotionally very stable, who played for guys like John Thompson and Louie Carnesecca. They were very mature, they’d been through the rigors of it. Now you’ve got guys who have been in college eight months. Winning is not a priority right away. It’s that second contract now and the whole total mind-set is totally different. It’s not much more difficult to coach at the NBA level than when I did it in 1987.”

Time not on their side

The long list of college coaches who failed — Pitino’s two seasons with New York in the 1980s, when he led the Knicks to 52 victories and the playoffs’ second round his final year there, often are forgotten — have done so because they by and large agreed to coach losing teams on relatively short-term contracts.

Saunders calls the Wolves’ situation different, saying his team isn’t hiring a coach from “a position of weakness” because it won 40 games this last season rather than 15 or 18.

Boston lured Stevens from Butler last summer with a six-year, $22 million contract that gives him financial security and, most importantly, time to adjust through his first pro seasons that brought a 25-57 record and plenty of lessons in his first one.

“That’ll help,” Adelman said. “That’ll help.”

Brown told reporters last summer that college coaches are the lone voice on their team. But they are most often doomed to fail in the NBA not because they lack expertise but because a franchise’s ownership, management and the coach often lack a shared vision and don’t speak with that one voice.

Celtics General Manager Danny Ainge said as much the day he introduced Stevens last July.

“Rick Pitino, John Calipari are fantastic basketball coaches,” Ainge said. “They didn’t fail because they can’t coach. The failure was from an organizational standpoint, not giving them patience, being supportive, [making correct] personnel decisions. Those guys could easily succeed in the NBA. We have to do this all together.”

Stevens conceivably has six years — and $22 million — to learn the differences between the two games’ length and number of games, their shot clocks and one’s immature teenagers and the other’s grown, rich and sometimes still immature men.

“It took me a while to learn the differences in the game,” Casey said. “It seems like 30 years ago, but you do learn the nuances and the personality of the NBA. You need time to get it together. If you’re building something, patience is very important. To have continuity, if you’re a college coach and you have time, you’ll figure it out.”