The deep passion for high school basketball in Maine impressed Jon Jennings.

The former Boston Celtics executive and assistant coach, who grew up surrounded by Hoosier Hysteria in Indiana, is tapping into that passion to bring what he believes will be the next successful professional sports franchise to Maine.

NBA Development League president Dan Reed will be in Portland on Wednesday to formally award the city a D-League franchise to begin play for the 2009-10 season.

“It’s been a long road, probably the culmination of 18 months of work. We’re ready to go,” said Bill Ryan Jr., owner of Oxford Plains Speedway, who is one of Jennings’ partners, along with Ryan’s father, Bill Ryan Sr., chairman of TD Banknorth.

The intimate Portland Expo will serve as the team’s home court. The season is expected to start the day after Thanksgiving.

The D-League (D for development) was started seven years ago to provide the NBA with a minor league structure similar to baseball and hockey. According to Jennings, 25 percent of the current NBA players have played in the D-League.

“In the old days, we used to dream of having something like the D-League,” Jennings said. “During my era, (the Celtics) had Bird, McHale and Parish. We were a pretty good team, and we’d be drafting toward the end of the first and second round. Those players would not see a lot of basketball time and during the course of an NBA season, you don’t have a lot of practice time, either. Having a minor league franchise to send your players down to to get training plus actual game experience would have been invaluable.”

There are currently 16 teams in the D-League. Each club is affiliated with two NBA teams, who stock up to two players each on the roster. Jennings is hopeful that the Boston Celtics will have their affiliation switched from the Utah Flash to Portland. The league will announce the affiliations after the current season.

Boston’s Gabe Pruitt, J.R. Giddens and Mikki Moore, who signed with the Celtics on Tuesday, have all played in the D-League.

Some of the better known players who have spent time in the D-League include Jordan Farmer of the Los Angeles Lakers, Chris Andersen of the Denver Nuggets and Bobby Simmons of the New Jersey Nets.

“The NBA likes to describe it as the second best basketball league in the world,” Ryan said. “It’s not guys from a men’s pickup league. It’s No. 1, No. 2 draft picks from the NBA that either just aren’t getting enough playing time for their NBA team or weren’t able to stick after training camp. They’re still working hard and trying to fulfill a need down the road for an NBA team.”

With his former association with the Celtics as an assistant coach, scouting coordinator and director of basketball operations, Jennings wanted to secure a place in New England to take advantage of the Celtics popularity. He found that in Portland.

“I was looking at various cities around New England, and once I found out about the fanatical love for high school basketball here in the state of Maine, that’s when I knew I found the right place,” Jennings said.

The group is already planning significant upgrades to the Expo. It has already purchased a new parquet floor for the Expo, and plan to add courtside seats and other amenities.

“We’re really excited about the Expo because of the intimacy of the building,” Ryan said.

Seating capacity for the Expo will be between 3,100-3,200. The team is looking to hold up to five doubleheaders at the Expo with Portland High School’s basketball team.

The bulk of the D-League franchises are located in the Midwest and West, with Erie, Pa., the closest to Portland. The league has said it hopes to expand into the Northeast, but it is unclear if any other team will join Portland for the 2009-10 season.

Professional basketball has tried to gain a foothold in Maine in the past. A couple of CBA teams played in Bangor more than 20 years ago, including the Maine Lumberjacks. In the mid 1990s, the USBL, a summer basketball league, lasted one year with the Portland Mountain Cats.

Ryan says the D-League’s association with the NBA makes this team different than those attempts.

The team will begin selling season tickets immediately by calling 207-210-6655. It is also starting a first-fan promotion for everyone who buys season tickets or fills out an official registration. More information is available on the team’s Web site, www.nbamaine.com.

A name-the-team contest will be announced soon.