Cleveland routed New York 101-83 on Sunday, leading by as many as 30 at one point.
New York shot 38 percent and missed 19 of its 22 three-point field goals attempts.
The Knicks have the worst record in the league at 10-45 and have lost seven straight games.
Jackson took over the Knicks last March, hired first-time coach Derek Fisher three months later and declared that the team would be in the playoffs. The Knicks then proceeded to lose 36 of their first 41 games, including a franchise record 16-game losing streak.
- Scooby Axson