Dallas ? Donnie Nelson didn’t waste much time voicing his displeasure about players who join the NBA after playing just one year of college ball.

“We’re not in the babysitting business,” the Dallas Mavericks’ president of basketball operations said.

Under terms of the collective bargaining agreement, the NBA allows athletes who have played at least one year at college to join its league as early entry draft candidates. But before he retired in February following a 30-year term as the NBA’s commissioner, David Stern attempted to get the National Basketball Player’s Association to agree that no one can play in the NBA until he’s at least 20 years old.

The issue of one-and-done players can be a contentious bargaining chip if either side opts out of the current CBA in 2017.

“My opinion, in an ideal world, is for guys to have the maturation of a college experience, and I think it’s better for the college product and better for our product if we get players that are more developed and older,” Nelson said. “That being said, there’s always the unique case that has to be addressed.

“But for the most part, for the overall good of college and pro basketball, I think it’s in both of our best interest to have players come in (to the NBA) with more college experience versus less.”

On the front end of the equation, one-and-done players basically rob a college program of the chance to develop a young player. On the back end, those players usually aren’t mentally or physically prepared to take on the numerous challenges involved with playing in the NBA, including handling finances, a wild travel schedule and dealing with experienced groupies and hangers-on.

College coaches, however, often are on the fence when it comes to having an extremely talented player on their rosters, even though they know that player likely will bolt to the NBA after just one season.

“Any time you can get a player that’s good enough to leave (college) after one year, he probably had some success and your team had some success,” Oklahoma State coach Travis Ford said. “I think it’s a tough situation especially for the coaches trying to develop some chemistry within your team and some continuity.”

The top one-and-dones expected to be chosen in Thursday’s NBA Draft include Duke’s Jabari Parker, Kentucky’s Julius Randle, Indiana’s Noah Vonleh and the Kansas duo of Andrew Wiggins and Joel Embiid. While those players are expected to be successful NBA players, they are the exception to the rule.

“I personally would prefer players that come to college, stay two years or three years,” Baylor coach Scott Drew said. “I just think in two years you’re socially and academically able to be more invested and grow more. But whatever the rule is, that’s what we’ll all adjust to.”

Ryan Blake, the senior director of NBA scouting operations, would like for the NBA to get out of the business of adjusting to one-and-done players.

“This is not the company NBA — this is my opinion — that when you have two years to evaluate a player, you bring in a better product,” Blake said.

The most celebrated one-and-done is Kevin Durant, who left Texas after his freshman season and was the No. 2 overall pick by Seattle, now the Oklahoma City Thunder, in the 2007 NBA Draft. But for every Durant, Blake and others know there are plenty of players not prepared for the NBA.

“You’ll have an unbelievable, once-in-a-million Durant franchise player,” Blake said. “But you’re going to have guys that you have to develop, and it takes time.”

Kareem Abdul-Jabbar, the NBA’s all-time leading scorer, also isn’t a fan of one-and-done players.

“I think one-and-done does not work,” Abdul-Jabbar said. “I think basically the NBA needs to raise the age up to 21 or something like that just to make sure that people can make this transition.

“I saw too many immature unprepared people coming straight out of high school — they didn’t have a chance. It wasn’t really a great opportunity for them because their lack of knowledge really worked against them.”

Mavericks free agent point guard Devin Harris, who spent three seasons at Wisconsin before declaring for the draft in 2004, sides with the players who can seek fame and fortune earlier if they bolt to the NBA after one year of college.

“I don’t necessarily blame them, especially the way the NCAA is,” Harris said. “I think it could be a good thing or a bad thing — it just depends on the person. You have certain guys that work out really well and certain guys that struggle. It depends on their maturity level.”

Ford summed up the plight of the college coaches, saying, “We all would like to have some one-and-done players, that’s for sure, if they’re good enough to do it. But at this point, it doesn’t do much good to complain about it. It is the rule, or it is what it is. And you’ve got to deal with.”