[1] He made the Senators lineup out of training camp to start the 2011–12 season, but was returned to Djurgårdens IF in Sweden after scoring one point in nine NHL games with Ottawa.

[8] He scored five goals and nine points,[8] which made him the third-most-successful junior player 18 years or younger in the organisation and playing with the senior team, behind Fredrik Bremberg and Jacob Josefson.

He registered his first career NHL point in his first game, an assist on a goal by Filip Kuba in a 5–3 loss to the Detroit Red Wings.

[11] In June 2012, Zibanejad was rumoured to be a key part of a package Ottawa was offering to the Columbus Blue Jackets in exchange for Rick Nash.

The offer was allegedly withdrawn when Columbus general manager Scott Howson informed the Senators Nash was unwilling to waive his no-trade clause to accept a move to Ottawa.

[13] Due to the NHL lockout, Zibanejad began the season with Binghamton, where he registered 11 points in 23 games while battling injuries.

The goal came on the power play against goaltender Peter Budaj and with assists from Colin Greening and André Benoit.

[17] On 20 November 2016, during a game against the Florida Panthers, Zibanejad suffered a gruesome injury in overtime when he went hard with his left leg into the boards while trying to get in front of Reilly Smith.

On 20 April 2017, Zibanejad scored the overtime winning goal in Game 5 of the 2017 NHL Eastern Conference quarterfinal against the Montreal Canadiens.

[21][22] After trading first-line centre Derek Stepan, the Rangers avoided arbitration with Zibanejad, signing him to a five-year, $26.75 million contract extension on 25 July 2017.

[22] The Rangers failed to make the playoffs for the first time since 2010,[23] and announced they were rebuilding and proceeded to jettison veteran players while retaining young talent like Zibanejad.

[35] After his hot start, Zibanejad missed time with an injury suffered after a high cross-check from Boston Bruins forward Patrice Bergeron.

[39] Among Zibanejad's tallies was the overtime winner, making him only the second player in NHL history to complete the quintet of goals in the extra period.

[43] He scored another hat trick a week later on 25 March in a subsequent game against the Flyers, a match the Rangers won 8–3.

[44] Accomplishing these feats, he became the third NHL player to score a natural hat trick in consecutive games against the same opponent in a single season after Thomas Vanek and Peter Bondra.

[45] On 25 April 2021, during a game against the Buffalo Sabres, Zibanejad scored his seventh career hat trick (third of the season).

On 5 January 2012, Zibanejad scored the gold medal-winning golden goal for Sweden in the 2012 World Junior Ice Hockey Championships against Russia in the tournament final; the game finished 1–0.

[64] Mehrdad, a Christian, left Iran in 1983 due to religious persecution following two years of mandatory military service in the Iran–Iraq War.

[66] Mika's maternal half-brother, Monir Kalgoum, is also an ice hockey player who played professionally for teams in several lower-tier European leagues, most notably Huddinge IK and AIK IF in Sweden's HockeyAllsvenskan and Milton Keynes Lightning in the United Kingdom.

He DJ'd a set, along with fire and pyrotechnics, on the second day (Friday night) of the three-day music festival in Sweden.