He affected games without looking at the basket, made pinpoint bounce passes in transition to teammates and often left fans wondering what he was going to do next. Jason Kidd was the ultimate point guard for much of his 19-year career in the N.B.A., but at the end of his one season with the Knicks, his magic was no more.

So it was not a surprise that the 40-year-old Kidd, the third-oldest player in the league, announced his retirement Monday with two years left on his contract with the Knicks. In his last month in a Knicks uniform, Kidd could barely put the ball in the basket. He did not score a point in the Knicks’ second-round playoff series against the Indiana Pacers, and he missed his last 18 shots of the postseason.

In the final two games against Indiana, Coach Mike Woodson played Kidd only 11 minutes.

“I’ve played the game for a long time,” Kidd said in a radio interview Monday on ESPN. “This was the time to move on.”

Kidd’s departure leaves three guards on the Knicks’ roster: Raymond Felton, J. R. Smith and Iman Shumpert. However, Smith is expected to opt out of his contract to pursue free agency and is not certain to return. Shumpert may be needed in the frontcourt.