Shanahan electrified the Madison Square Garden fans in the second period with a breakaway goal that gave New York a 3-1 lead in its season opener against Washington.
He reached the milestone in more typical fashion, putting a puck in from in front of the net during a delayed-penalty call at 2:58 of the third.
Shanahan joined the Rangers this summer after a long stint with the Detroit Red Wings that produced three Stanley Cup titles. The 37-year-old left wing signed a one-year deal worth $4 million after scoring 40 goals and 81 points in his final season in Hockeytown.
In 1,351 NHL games, Shanahan has 634 assists.