Although he remained undrafted throughout his years of eligibility, Goodrow was invited to attend the San Jose Sharks' Development Camp and subsequently signed with them.

During his tenure with the Sharks, he played with their American Hockey League affiliate, the San Jose Barracuda, and helped them win their first series during the 2017 Calder Cup playoffs.

On July 17, 2021, with Goodrow approaching free agency, his signing rights were traded by Tampa Bay to the New York Rangers in exchange for a seventh-round pick in the 2022 NHL entry draft.

[2] At the age of 15 with the York Simcoe Express, Goodrow finished second in OMHA/Eastern AAA Hockey League scoring with 67 goals and 47 assists for 114 points in 71 games.

[4] As a result of his play at the junior level, Goodrow was a first-round pick of the Brampton Battalion in the 2009 Ontario Hockey League (OHL) Priority Selection.

[6] He eventually cemented himself into a right wing role alongside Sam Carrick and Sean Jones while veterans Cody Hodgson and Matt Duchene attended National Hockey League (NHL) training camps.

[9] After tallying four goals and three assists for seven points through 22 games, Goodrow was chosen to represent Team Canada at the World U-17 Hockey Challenge.

[11] Goodrow subsequently missed three OHL games while playing at the 10-team World U-17 Hockey Challenge and returned with a silver medal.

[16] During the offseason prior to the 2011–12 season, Goodrow and teammates Philip Lane and Ian Watters spent time in the gym and working with a skating coach on strength and conditioning.

[21][22] Goodrow maintained his career-best season and in March ranked second in Battalion scoring with 25 goals and 22 assists for 47 points.

ESPN reporter Grant Sonier stated: "It was really evident when he played on that line at a really high pace -- the Russians were a really good team -- and (his skating) was the issue.

[30] Goodrow returned from the Detroit Red Wings camp the day before the 2013–14 season and began his second campaign as the Battalion's team captain.

[31] On September 22, Goodrow played in his 253rd OHL game to tie Wojtek Wolski and John de Gray for fifth place on the franchise’s all-time list.

[50] As a result of his improvements, Goodrow re-joined the Sharks for their 2016 Stanley Cup playoffs push against the St. Louis Blues and Pittsburgh Penguins.

[47] He was again invited to participate in the Sharks' training camp and exhibition games, where he played alongside Tommy Wingels and Melker Karlsson,[51] but was re-assigned to the AHL.

[53] His versatile play over his two full seasons with the Barracuda was recognized by head coach Roy Sommer who said: "Barclay’s turned into an all-around player for us.

In his second game with the team, he centered a line for the first time since he was in minor hockey as he helped lead the Sharks to their fourth consecutive win.

[63] As the Sharks qualified for the 2019 Stanley Cup playoffs, Goodrow was tasked with centering their fourth line with Lukas Radil and Melker Karlsson.

[64] During Game 7 of the Sharks' first-round matchup against the Vegas Golden Knights, Goodrow scored the series-winning goal in overtime to lead them to the second round.

[66] Upon joining the team, Goodrow skated on the right wing on Tampa Bay's third line alongside Ondrej Palat and Tyler Johnson.

[77] In the Lightnings final game of the regular season, it was announced that Goodrow was recovering from an upper body injury with no returning timeline.

[78] Goodrow eventually returned to the Lightning's lineup for Game 6 against the Florida Panthers and logging three shots on goal and five hits in 16:43 minutes of ice time.

[84] On July 17, 2021, with Goodrow approaching free agency, his signing rights were traded by Tampa Bay to the New York Rangers in exchange for a seventh-round pick in the 2022 NHL Entry Draft.

[85] Upon joining the team, Rangers GM Chris Drury praised his ability to be versatile, saying: "I could see him do all different things for Gerard, whether that's more time in the middle, whether it's face-offs in the [defensive] zone.

[92] On January 24, Goodrow scored his 40th career NHL goal to help the Rangers beat the Los Angeles Kings.

[96] Due to injuries to the Rangers lineup, Goodrow began the 2022–23 season alternating between fourth-line center and third-line winger.

[99] Near the end of the season, Goodrow gained Jimmy Vesey and Tyler Motte as his linemates and the trio combined for four goals over their first 12 games together.

[101] Entering the 2024 offseason unable to meet expectations the past several years from his high-value contract relative to his performance, the Rangers looked to move Goodrow but had difficulty given his high salary and 15 team no trade list.

[104] Goodrow was reportedly unhappy with the move, as he was not approached by the Rangers management to help facilitate a trade and had placed San Jose on his no-trade list.