The refs stopped the game and a brief ceremony was held for Jennings who is the first Arlington student athlete to reach the 1,000 point plateau since 2003.
"It was just all overwhelming," said Jennings. "I tried not to focus on it, [I] just came out and played."
The milestone basket, which Jennings scored with 6:11 left to in the second quarter, put the Eagles (1-10) on top 32-13 - 17 of which belonged to him.
The Presidents (1-12) did not have an answer for Jennings all night as he led all scorers with 38 points and added 18 rebounds and 4 blocks en route to an 81-67 win - their first of the season.
Jennings now has 1,022 points in his career.
"It's good for us to get a win first and foremost, but DJ, he's a man child out there. He's a big kid and he knows how to use it, which is great," said Arlington coach Chris Taft. "We know that we want to get him the ball and I think his teammates did a good job of focusing on him getting the ball inside tonight, especially early."
The team got Jennings involved from the outset when sophomore guard Austin Hawley found him underneath the basket, which set up an and one to put Arlington on top 3-0.
The Eagles outscored the Presidents 25-11 in the first quarter with Jennings leading the way with 11 points.
"I couldn't have done it without them," said Jennings of teammates when asked about reaching the milestone.
Led by seniors Matthew Covell - who scored 17 points and was one rebound shy of the double double - and Ben Veysey, the Presidents began to come alive in the second half, scoring 18 points in the third period. But it was not enough as Jennings scored 12 of the team's 17 third quarter points to give the Eagles a comfortable 63-42 lead heading into the final stanza.
With Jennings sitting for a decent portion of the fourth, the Presidents scored outscored the Eagles 23-16 led by Veysey who had 11 of his 22 points in the quarter. In the end though the lead simply proved too much for the Presidents to overcome.
"We just came out a little slow today. We were a little bit scared with DJ being so big," said Black River coach Bobby Rohrig. "After the 17-2 start that Arlington had we started playing right with them, but it just took us a little bit too long to feel like we had the confidence to go inside and play our game."
Hawley - who led the team in the fourth quarter with six points - had 14 points and 6 rebounds for the Eagles and sophomore Nathan Mattison had 15 points.
"Nathan Mattison, he can be a lethal scorer," said Taft. "He's got a great jump shot. He's just one of those kids whose young and he needs to be more aggressive and we're working on that everyday. We need three people in double figures to compete in games and tonight we got that."
The Arlington boys will be on the road on Wednesday to take on Division II Springfield (3-11). The game begins at 7 p.m.