George Washington, now led by Mike Lonergan, has met George Mason on the basketball court just 12 times in 38 years. (Matt McClain/FOR THE WASHINGTON POST)

The George Mason and George Washington men’s basketball programs have followed parallel but separate paths for decades.

Some 20 miles apart and existing in the long shadows of Maryland and Georgetown, they have operated on the edge of the glamour conferences in different circuits, attracting players of similar caliber and making periodic NCAA tournament appearances. But despite the similarity and proximity, they have crossed paths just 12 times in 38 years.

With George Mason’s summer transfer from the Colonial Athletic Association to the Atlantic 10, George Washington’s playpen since 1976, the landscape has changed. And in a college basketball hotbed lacking homegrown rivalries, both parties foresee a blossoming relationship.

“There is a natural attraction to that game because people hopefully are going to say: ‘That is really neat. I wish more schools in this area were playing each other,’ ” GMU Athletic Director Tom O’Connor said. “It’s a game that isn’t any more important than the others, but it’s close by, and it’s going to be a lot of fun.”

The teams will collide Jan. 25 at Patriot Center and March 2 at Smith Center — both weekend games carried by NBC Sports Network.

Aside from American and Navy in the lower-tier Patriot League, no other Division I teams in the immediate Washington area share a conference.

“At first, I was like, ‘Oh, I kind of like being the only local team’ ” in the Atlantic 10, said Colonials Coach Mike Lonergan, who is starting his third season in Foggy Bottom. “But you know what? In Philly, they all play each other. It’s the best. It’s going to help with media attention and crowds. Mason is going to be great for us and it’s going to be a healthy rivalry.”

The athletic departments did arrange regular season meetings in the 2009-10 and 2010-11 seasons, with each team winning easily at home. But the games were held on weeknights in December and, without conference ramifications or a long-term relationship, the buzz was short-lived.

The dynamic changed in the spring, when, after two years of wooing, George Mason accepted the Atlantic 10’s invitation. The move ended a three-decade affiliation with the CAA and its predecessor, the ECAC South, and provided the Patriots with a larger national platform.

Patriots Coach Paul Hewitt believes the new local rivalry and renewed regional clashes will benefit recruiting.

“You create some excitement,” he said. “We might have two sellouts with GW. We bring a kid to that game, it’s an exciting atmosphere. It’s going to help keep local players in the area. We should be keeping kids between Baltimore and Richmond.”

Like many conferences, the Atlantic 10 has changed shape in recent years. While George Mason arrived, heavyweights Butler, Temple and Xavier departed along with Charlotte. (Davidson will hop aboard next year.) GW, Duquesne and Massachusetts are the last remaining founding members.

The competition between Mason and GW will reach beyond basketball. Last month the universities created the Revolutionary Rivalry, with points awarded for victories in each of 16 sports. To the winner goes the Tri-Corner Hat Trophy.

With neither fielding a football program, most eyes will turn to the court.

“People are starting to talk about it. Hopefully we become good rivals,” said GW sophomore guard Kethan Savage, an Episcopal High School graduate from Fairfax who attended George Mason games regularly with his uncle. He played AAU basketball with Patriots sophomore guard Patrick Holloway (Paul VI Catholic).

Savage was recruited to GW by Roland Houston, then a Colonials assistant. When GW fired Karl Hobbs in 2011, Houston moved to George Mason. His nephew, GW recruit Erik Copes, followed.

The 6-foot-8, 250-pound junior forward was slowed by a hip injury his first two seasons. Copes, however, is serving a six-game suspension for a violation of athletic department policy — the second straight year he has missed the start of the season for disciplinary reasons.

“It disappoints me,” Hewitt said. “He is a college kid who made a bonehead decision. We have rules. He is going to pay the consequences. He will get better for it.”

Neither the Patriots (22-16 last season) nor Colonials (13-17) are among the conference favorites, selected eighth and 10th, respectively, in the 13-team league. And while GW has not enjoyed a 20-win campaign since 2006-07, George Mason, a CAA titan for 10 years and Final Four surprise in 2006, finds itself without the usual expectations.

Both teams, though, return every starter and could emerge as contenders. The Colonials are young: Eight of 13 players are freshmen or sophomores. Conversely, Hewitt will start four seniors and a junior.

Experience will help ease the transition for the Patriots, who will confront a higher caliber of competition in their new league.

“We have a senior team coming back. It was the right time to make the move,” O’Connor said. “We have a terrific coach and players who have played against stiff competition. I am very optimistic. The reason we went to the Atlantic 10 wasn’t for just one year; this is just the launch and we want to sustain it for years to come.”