After debuting with the Blackhawks the following season, he briefly joined the team's minor league affiliate before becoming a full-time member of the roster beginning in 2013.

Internationally, Saad has represented the United States in several youth tournaments and captured a gold medal for the nation in the 2010 IIHF World U18 Championships.

However, the coach of the Rams acknowledged that it was not likely Saad would remain at Pine-Richland High School because he was being scouted by the USA Hockey National Team Development Program (NTDP).

[14][15] Instead of immediately joining the OHL, Saad and his older brother played the 2008–09 season with the Mahoning Valley Phantoms in the North American Hockey League (NAHL).

[25] After being ranked eighth among North American skaters by the NHL Central Scouting Bureau in January[26] Saad was named to Team Orr for the CHL Top Prospects game.

[29] After impressing the coaching staff during the Blackhawks' training camp, Saad signed a three-year, entry-level contract with the team on October 4, 2011.

Although he would miss all of November due to a hand injury, Saad recovered in time to join Team USA at the 2012 World Junior Ice Hockey Championships in December.

[36] He finished the regular season leading the league with 1.73 points per game as he helped th Spirit climb from ninth place to fourth in the conference standings.

[45] Saad returned to the Blackhawks training camp ahead of the 2012–13 season but was reassigned to their American Hockey League (AHL) affiliate, the Rockford IceHogs, in anticipation of the 2012–13 NHL lockout.

[56] As a result of his successful season, Saad was named as a finalist for the 2013 Calder Memorial Trophy as the NHL's top rookie, which eventually was given to Florida Panthers winger Jonathan Huberdeau.

[58] When the Blackhawks qualified for the 2013 playoffs and clinching the Presidents' Trophy as the best regular season team, Saad continued to remain on their top line with Toews and Hossa.

In Game 1 of their first round series against the eighth seeded Minnesota Wild, Saad played 21 minutes and had two shots on net to help lift the Blackhawks to a 2–1 overtime win.

[79] Although Saad was moved to the second line alongside Handzuš and Kane, the Blackhawks eliminated the Wild in six games and met with the Los Angeles Kings in the Western Conference Finals for the second straight year.

[93] His goal helped the Blackhawks lead the series at 3–1 and they eventually eliminated the Predators in six games to advance to the Western Conference Second Round against the Minnesota Wild.

Although his hometown team, the Pittsburgh Penguins wished to acquire him, Saad's negotiation rights were traded to the Columbus Blue Jackets on June 30, 2015.

[100] Along with his negotiation rights, the Blue Jackets also received Alex Broadhurst and Michael Paliotta in exchange for Jeremy Morin, Marko Daňo, Artem Anisimov, Corey Tropp and a fourth-round draft pick in 2016.

[106] Despite his slow start, Saad was projected to earn his first NHL All-Star Game selection as he quickly tallied the most power-play goals in the division by November 18.

[106] From December 17 to January 2, Saad tallied seven goals and six assists during a career-high seven-game point streak[106] while also leading the NHL with 28 backhand shots and tied for second with four.

[127] The Blue Jackets qualified for the 2017 Stanley Cup playoffs where they faced his hometown team, the defending champions, the Pittsburgh Penguins, in the first round.

[131] He immediately rejoined Jonathan Toews on the top line alongside Richard Pánik, who had replaced Marian Hossa, on the right.

[138] On November 25, Saad tied a franchise record for most shots in a period with seven while tallying his eighth goal of the season in a win over the Florida Panthers.

[141] Saad's production began to pick back up in January as Vinnie Hinostroza joined the Blackhawks top line on the right side of Toews.

[158] During the Blackhawks' 2019 training camp, Saad was reunited with Jonathan Toews and Dominik Kubalík as their first line left winger and the trio immediately developed chemistry together.

[163] He returned to the Blackhawks lineup on January 18 for their game against the Toronto Maple Leafs, playing 17:08 of ice time and tallying his 12th goal of the season.

[163] On October 10, 2020, the Blackhawks traded Saad away for a second time in his career, along with Dennis Gilbert, to the Colorado Avalanche in exchange for Nikita Zadorov and Anton Lindholm.

'[168] Saad made his debut with the Avalanche in the season opener on January 13, 2021, while playing on the right wing alongside Nazem Kadri and Gabriel Landeskog on the second line.

[169] After the Avalanche fell 4–1 to the St. Louis Blues, Saad was returned to his usual left wing position with Kadri at the centre and Andre Burakovsky on the right.

[184] After the Golden Knights tied the series 2–2, coach Jared Bednar placed Saad on the first line with Nathan MacKinnon and Mikko Rantanen for Game 6.

[185] As a free agent, Saad was signed to a five-year, $22.5 million contract by the Avalanche's divisional rival, the St. Louis Blues, on July 29, 2021.

"[193] After missing the first three games of the 2024–25 season due to the birth of his third child, Saad scored his 500th career NHL point on October 22 against the Winnipeg Jets.