He would score his first career Stanley Cup playoff goal on May 6, 2013, during game four of Detroit's Western Conference quarterfinal series against the Anaheim Ducks.

On June 29, 2017, Smith agreed to forfeit his impending free agent status in signing to a four-year, $17.4 million contract to remain with the Rangers.

On February 8, 2018, the Rangers placed Smith on waivers due to his struggling play,[8] and then assigned him to their AHL affiliate, the Hartford Wolf Pack after he went unclaimed.

[9] Shortly after arriving in Hartford, Smith broke his hand in a fight with teammate Vinni Lettieri during a practice, ending his season.

[10] In the 2018 season, under new head coach David Quinn, Smith saw an improved play and fewer penalties with reduced ice time.

In the 2019–20 season, Smith played exclusively as a winger before switching back to defenceman permanently after the Rangers traded Brady Skjei.