[1] Staal played for Team Canada in the 2006 and 2007 IIHF World Junior Ice Hockey Championships, bringing home gold medals both times.

This prestigious award was previously won by future NHL players Chris Pronger, Al MacInnis and Denis Potvin.

On May 13, 2007, although his Sudbury team lost the OHL Championship Series to the Plymouth Whalers in six games, Staal was named the winner of the Wayne Gretzky 99 Award, which goes to the League's post-season most valuable player (MVP).

[2] On October 4, 2007, Staal made his National Hockey League debut for the New York Rangers, as well as for Head Coach Tom Renney, who would use him in that first season primarily in a defensive role.

His wrist shot from the left faceoff circle sailed over the outstretched glove of goaltender Martin Brodeur and deflected in off the crossbar.

During 2007–08, Staal was one of 16 rookies selected to participate in the YoungStars competition at the 2008 NHL All-Star Game in Atlanta, where he scored a goal and added an assist.

[3] Staal finished his rookie season with ten points on the strength of two goals and eight assists; he also established himself as a reliable defender, posting a positive plus/minus rating at +2, as the Rangers qualified for the Stanley Cup playoffs.

The Rangers would again qualify for the Stanley Cup playoffs on the strength of their strong finish, but this time were defeated in the first round by the Washington Capitals in seven games after blowing a 3–1 series lead.

In the summer of 2009, Marc and his brothers Eric and Jordan were invited to try out for a Team Canada roster spot for the 2010 Winter Olympics in Vancouver.

In his third NHL season, Staal began to transition into more of a two-way role for the Rangers during 2009–10 as the development of his offence continued under John Tortorella.

He saved his finest for late in the year, scoring a beautiful, coast-to-coast goal against Florida Panthers goaltender Scott Clemmensen on April 3, 2010, after receiving the puck from teammate Henrik Lundqvist in the defensive zone.

[6] After a strong training camp, John Tortorella recognized Staal's leadership qualities in October 2010 by naming him an alternate captain at the age of 23.

In Game 5 of the Eastern Conference Semifinals against the Washington Capitals, Staal scored a memorable overtime goal to give the Rangers a 3–2 win.

After teammate Brad Richards had scored a rebound goal with 6.6 seconds left in regulation to send the game to overtime, Staal's powerplay slapshot from the point past Braden Holtby gave the Rangers a 3–2 win and a 3–2 series lead.

On September 26, 2020, Staal, as one of the longest-tenured players in Rangers history, ended his affiliation with the team as he was traded to the Detroit Red Wings, along with a 2021 second-round pick, in exchange for future considerations.

[16] In March 2023, Marc, along with his brother Eric, refused to wear Pride-themed jerseys in the pre-game warmups as a part of the Panthers' annual Pride Night; they cited their Christian faith as the reason for their decision.

[18] Following the 2023–24 season, Staal announced his retirement from ice hockey on September 5, 2024, and returned to the New York Rangers as a player development assistant.