Ullmark is expected to start at home in Thursday's preseason game against Buffalo, per Bruce Garrioch of Postmedia.
Ullmark posted a 22-10-7 record, 2.58 GAA and .915 save percentage in 40 contests with the Bruins in 2023-24. He was dealt to Ottawa over the summer and is set to begin the campaign as the Senators' clear No. 1 goaltender. Anton Forsberg will likely enter the season as the backup netminder, but Mads Sogaard is also challenging for the role of Ullmark's understudy.