Walker then took the road less traveled for young Canadian hockey players and traveled south of the border to play college hockey for Bowling Green State University. In the defenseman's four-year stay, Walker put up both points and penalty minutes. In his 160-game collegiate career, Walker recorded 60 points (22-38=60) and 250 penalty minutes.
Walker's stand-out play did not go unnoticed both at school and within the Kings organization. At school, Walker was named the captain of BGSU for both his junior and senior season. Then, following his career at BGSU, Walker, signed with the Ontario Reign.
As Walker had done in college, the defenseman continued to produce, posting 28 points (7-21=28), a plus-17 rating and 59 penalty minutes. Among team defensemen, he ranked first in points, assists, plus/minus, and ranked second in goals. He also totaled two points (1-1=2) in four postseason games with the Reign.
On July 3, 2018, the undrafted Keswick-born defenseman signed an entry-level contract with the Kings. To no surprise, it took Walker just 22 games in the 2018-19 season to get the call up to the big club. On October 23, 2018, Walker made his NHL debut with the Kings when they faced off against the Dallas Stars. In just over 13 minutes of ice time, Walker recorded his first assist in his NHL debut.
