"I appreciate all the hard work and determination Jaren has put into our program over the last two years," Seton Hall coach Kevin Willard said in a release. "He is an outstanding young man, and I wish him all the best in his future endeavors."
Sina, a 6-foot-2 New Jersey native, was averaging 7.0 points and 2.3 assists this season. He started 23 of 24 games, scoring nine points in 29 minutes against Georgetown on Tuesday.
Seton Hall didn't provide a reason for Sina's departure, only saying the sides had agreed to part ways.
"I tried my best," Sina told the Asbury Park Press. "I think I was a good teammate. I've always been positive. I've always worked hard. I always gave it 100 percent. It's not a good situation for me right now. At the end of the day, I think it's best for me and my family."
Seton Hall has lost six of its last eight games, including Tuesday's 19-point home defeat to Georgetown. Following the game, Willard closed the locker room to reporters and wouldn't address possible friction between factions of the team.
"I'm not going to talk about chemistry issues," he said in his postgame news conference.
The Pirates (15-9, 5-7 Big East) visit Providence on Saturday.