He made his National Hockey League debut on April 8, 2023, for the Toronto Maple Leafs after substituting for goaltender Ilya Samsonov with 1:10 remaining in the third period against the Montreal Canadiens.
[4] He spent the 2019–2020 season with the Prince George Spruce Kings of the British Columbia Junior Hockey League.
Alexander committed to the University of Toronto Varsity Blues' men's hockey team in May 2020 for the 2020–2021 season,[5] which was ultimately cancelled due to the COVID-19 pandemic.
[10] He held the role for the duration of the first period until Colorado Eagles goaltender Justus Annunen made it to Scotiabank Arena.
[13][14] With one minute and ten seconds remaining in the third period, and Toronto leading 7–1, Alexander was substituted in place of Samsonov.